GCC Code Coverage Report

Line	Branch	Exec	Source
1			//
2			// Copyright (c) 2019 Vinnie Falco (vinnie.falco@gmail.com)
3			// Copyright (c) 2022 Alan de Freitas (alandefreitas@gmail.com)
4			//
5			// Distributed under the Boost Software License, Version 1.0. (See accompanying
6			// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
7			//
8			// Official repository: https://github.com/boostorg/url
9			//
10
11			#ifndef BOOST_URL_URL_BASE_HPP
12			#define BOOST_URL_URL_BASE_HPP
13
14			#include <boost/url/detail/config.hpp>
15			#include <boost/url/ipv4_address.hpp>
16			#include <boost/url/ipv6_address.hpp>
17			#include <boost/url/params_encoded_ref.hpp>
18			#include <boost/url/params_ref.hpp>
19			#include <boost/url/pct_string_view.hpp>
20			#include <boost/url/scheme.hpp>
21			#include <boost/url/segments_encoded_ref.hpp>
22			#include <boost/url/segments_ref.hpp>
23			#include <boost/url/url_view_base.hpp>
24			#include <cstdint>
25			#include <initializer_list>
26			#include <memory>
27			#include <string>
28			#include <utility>
29
30			namespace boost {
31			namespace urls {
32
33			#ifndef BOOST_URL_DOCS
34			namespace detail {
35			struct any_params_iter;
36			struct any_segments_iter;
37			struct params_iter_impl;
38			struct segments_iter_impl;
39			struct pattern;
40			}
41			#endif
42
43			/** Common functionality for containers
44
45			This base class is used by the library
46			to provide common member functions for
47			containers. This cannot be instantiated
48			directly; Instead, use one of the
49			containers or functions:
50
51			@par Containers
52			@li @ref url
53			@li @ref url_view
54			@li @ref static_url
55
56			@par Functions
57			@li @ref parse_absolute_uri
58			@li @ref parse_origin_form
59			@li @ref parse_relative_ref
60			@li @ref parse_uri
61			@li @ref parse_uri_reference
62			*/
63			class BOOST_URL_DECL
64			url_base
65			: public url_view_base
66			{
67			char* s_ = nullptr;
68			std::size_t cap_ = 0;
69
70			friend class url;
71			friend class static_url_base;
72			friend class params_ref;
73			friend class segments_ref;
74			friend class segments_encoded_ref;
75			friend class params_encoded_ref;
76			friend struct detail::pattern;
77
78			struct op_t
79			{
80			~op_t();
81			op_t(url_base&,
82			core::string_view* = nullptr,
83			core::string_view* = nullptr) noexcept;
84			void move(char*, char const*,
85			std::size_t) noexcept;
86
87			url_base& u;
88			core::string_view* s0 = nullptr;
89			core::string_view* s1 = nullptr;
90			char* old = nullptr;
91			};
92
93		11076	virtual ~url_base() noexcept = default;
94		4038	url_base() noexcept = default;
95			url_base(detail::url_impl const&) noexcept;
96			explicit url_base(core::string_view);
97			void reserve_impl(std::size_t n);
98			void copy(url_view_base const&);
99			virtual void clear_impl() noexcept = 0;
100			virtual void reserve_impl(
101			std::size_t, op_t&) = 0;
102			virtual void cleanup(op_t&) = 0;
103
104			public:
105			//--------------------------------------------
106			//
107			// Observers
108			//
109			//--------------------------------------------
110
111			/** Return the url as a null-terminated string
112
113			This function returns a pointer to a null
114			terminated string representing the url,
115			which may contain percent escapes.
116
117			@par Example
118			@code
119			assert( std::strlen( url( "http://www.example.com" ).c_str() ) == 22 );
120			@endcode
121
122			@par Complexity
123			Constant.
124
125			@par Exception Safety
126			Throws nothing.
127			*/
128			char const*
129		17509	c_str() const noexcept
130			{
131		17509	return pi_->cs_;
132			}
133
134			/** Return the number of characters that can be stored without reallocating
135
136			This does not include the null terminator,
137			which is always present.
138
139			@par Complexity
140			Constant.
141
142			@par Exception Safety
143			Throws nothing.
144			*/
145			std::size_t
146		8	capacity() const noexcept
147			{
148		8	return cap_;
149			}
150
151			/** Clear the contents while preserving the capacity
152
153			@par Postconditions
154			@code
155			this->empty() == true
156			@endcode
157
158			@par Complexity
159			Constant.
160
161			@par Exception Safety
162			No-throw guarantee.
163			*/
164			void
165		119	clear() noexcept
166			{
167		119	this->clear_impl();
168		119	}
169
170			/** Adjust the capacity without changing the size
171
172			This function adjusts the capacity
173			of the container in characters, without
174			affecting the current contents. Has
175			no effect if `n <= this->capacity()`.
176
177			@par Exception Safety
178			Strong guarantee.
179			Calls to allocate may throw.
180
181			@throw bad_alloc Allocation failure
182
183			@param n The capacity in characters,
184			excluding any null terminator.
185			*/
186			void
187		149	reserve(std::size_t n)
188			{
189		149	reserve_impl(n);
190		148	}
191
192			//--------------------------------------------
193			//
194			// Fluent API
195			//
196
197			//--------------------------------------------
198			//
199			// Scheme
200			//
201			//--------------------------------------------
202
203			/** Set the scheme
204
205			The scheme is set to the specified
206			string, which must contain a valid
207			scheme without any trailing colon
208			(':').
209			Note that schemes are case-insensitive,
210			and the canonical form is lowercased.
211
212			@par Example
213			@code
214			assert( url( "http://www.example.com" ).set_scheme( "https" ).scheme_id() == scheme::https );
215			@endcode
216
217			@par Complexity
218			Linear in `this->size() + s.size()`.
219
220			@par Exception Safety
221			Strong guarantee.
222			Calls to allocate may throw.
223			Exceptions thrown on invalid input.
224
225			@throw system_error
226			`s` contains an invalid scheme.
227
228			@param s The scheme to set.
229
230			@par BNF
231			@code
232			scheme = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
233			@endcode
234
235			@par Specification
236			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.1">
237			3.1. Scheme (rfc3986)</a>
238
239			@see
240			@ref remove_scheme.
241			*/
242			url_base&
243			set_scheme(core::string_view s);
244
245			/** Set the scheme
246
247			This function sets the scheme to the specified
248			known @ref urls::scheme id, which may not be
249			@ref scheme::unknown or else an exception is
250			thrown. If the id is @ref scheme::none, this
251			function behaves as if @ref remove_scheme
252			were called.
253
254			@par Example
255			@code
256			assert( url( "http://example.com/echo.cgi" ).set_scheme_id( scheme::wss ).buffer() == "wss://example.com/echo.cgi" );
257			@endcode
258
259			@par Complexity
260			Linear in `this->size()`.
261
262			@par Exception Safety
263			Strong guarantee.
264			Calls to allocate may throw.
265			Exceptions thrown on invalid input.
266
267			@throw system_error
268			The scheme is invalid.
269
270			@param id The scheme to set.
271
272			@par Specification
273			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.1">
274			3.1. Scheme (rfc3986)</a>
275			*/
276			url_base&
277			#ifndef BOOST_URL_DOCS
278			set_scheme_id(urls::scheme id);
279			#else
280			set_scheme_id(scheme id);
281			#endif
282
283			/** Remove the scheme
284
285			This function removes the scheme if it
286			is present.
287
288			@par Example
289			@code
290			assert( url("http://www.example.com/index.htm" ).remove_scheme().buffer() == "//www.example.com/index.htm" );
291			@endcode
292
293			@par Postconditions
294			@code
295			this->has_scheme() == false && this->scheme_id() == scheme::none
296			@endcode
297
298			@par Complexity
299			Linear in `this->size()`.
300
301			@par Exception Safety
302			Throws nothing.
303
304			@par BNF
305			@code
306			URI = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
307			@endcode
308
309			@par Specification
310			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.1">
311			3.1. Scheme (rfc3986)</a>
312
313			@see
314			@ref set_scheme.
315			*/
316			url_base&
317			remove_scheme();
318
319			//--------------------------------------------
320			//
321			// Authority
322			//
323			//--------------------------------------------
324
325			/** Set the authority
326
327			This function sets the authority
328			to the specified string.
329			The string may contain percent-escapes.
330
331			@par Example
332			@code
333			assert( url().set_encoded_authority( "My%20Computer" ).has_authority() );
334			@endcode
335
336			@par Exception Safety
337			Strong guarantee.
338			Calls to allocate may throw.
339			Exceptions thrown on invalid input.
340
341			@throw system_eror
342			The string contains an invalid percent-encoding.
343
344			@param s The authority string to set.
345
346			@par BNF
347			@code
348			authority = [ userinfo "@" ] host [ ":" port ]
349
350			userinfo = *( unreserved / pct-encoded / sub-delims / ":" )
351			host = IP-literal / IPv4address / reg-name
352			port = *DIGIT
353			@endcode
354
355			@par Specification
356			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2">
357			3.2. Authority (rfc3986)</a>
358			@see
359			@ref remove_authority.
360			*/
361			url_base&
362			set_encoded_authority(
363			pct_string_view s);
364
365			/** Remove the authority
366
367			This function removes the authority,
368			which includes the userinfo, host, and
369			a port if present.
370
371			@par Example
372			@code
373			assert( url( "http://example.com/echo.cgi" ).remove_authority().buffer() == "http:/echo.cgi" );
374			@endcode
375
376			@par Postconditions
377			@code
378			this->has_authority() == false && this->has_userinfo() == false && this->has_port() == false
379			@endcode
380
381			@par Complexity
382			Linear in `this->size()`.
383
384			@par Exception Safety
385			Throws nothing.
386
387			@par BNF
388			@code
389			authority = [ userinfo "@" ] host [ ":" port ]
390
391			userinfo = *( unreserved / pct-encoded / sub-delims / ":" )
392			host = IP-literal / IPv4address / reg-name
393			port = *DIGIT
394			@endcode
395
396			@par Specification
397			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2">
398			3.2. Authority (rfc3986)</a>
399
400			@see
401			@ref set_encoded_authority.
402			*/
403			url_base&
404			remove_authority();
405
406			//--------------------------------------------
407			//
408			// Userinfo
409			//
410			//--------------------------------------------
411
412			/** Set the userinfo
413
414			The userinfo is set to the given string,
415			which may contain percent-escapes.
416			Any special or reserved characters in the
417			string are automatically percent-encoded.
418			The effects on the user and password
419			depend on the presence of a colon (':')
420			in the string:
421
422			@li If an unescaped colon exists, the
423			characters up to the colon become
424			the user and the rest of the characters
425			after the colon become the password.
426			In this case @ref has_password returns
427			true. Otherwise,
428
429			@li If there is no colon, the user is
430			set to the string. The function
431			@ref has_password returns false.
432
433			@note
434			The interpretation of the userinfo as
435			individual user and password components
436			is scheme-dependent. Transmitting
437			passwords in URLs is deprecated.
438
439			@par Example
440			@code
441			assert( url( "http://example.com" ).set_userinfo( "user:pass" ).encoded_user() == "user" );
442			@endcode
443
444			@par Complexity
445			Linear in `this->size() + s.size()`.
446
447			@par Exception Safety
448			Strong guarantee.
449			Calls to allocate may throw.
450
451			@param s The string to set.
452
453			@par BNF
454			@code
455			userinfo = [ [ user ] [ ':' password ] ]
456
457			user = *( unreserved / pct-encoded / sub-delims )
458			password = *( unreserved / pct-encoded / sub-delims / ":" )
459			@endcode
460
461			@par Specification
462			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.1">
463			3.2.1. User Information (rfc3986)</a>
464
465			@see
466			@ref remove_userinfo,
467			@ref set_encoded_userinfo.
468			*/
469			url_base&
470			set_userinfo(
471			core::string_view s);
472
473			/** Set the userinfo.
474
475			The userinfo is set to the given string,
476			which may contain percent-escapes.
477			Escapes in the string are preserved,
478			and reserved characters in the string
479			are percent-escaped in the result.
480			The effects on the user and password
481			depend on the presence of a colon (':')
482			in the string:
483
484			@li If an unescaped colon exists, the
485			characters up to the colon become
486			the user and the rest of the characters
487			after the colon become the password.
488			In this case @ref has_password returns
489			true. Otherwise,
490
491			@li If there is no colon, the user is
492			set to the string. The function
493			@ref has_password returns false.
494
495			@note
496			The interpretation of the userinfo as
497			individual user and password components
498			is scheme-dependent. Transmitting
499			passwords in URLs is deprecated.
500
501			@par Example
502			@code
503			assert( url( "http://example.com" ).set_encoded_userinfo( "john%20doe" ).user() == "john doe" );
504			@endcode
505
506			@par Complexity
507			Linear in `this->size() + s.size()`.
508
509			@par Exception Safety
510			Strong guarantee.
511			Calls to allocate may throw.
512			Exceptions thrown on invalid input.
513
514			@throw system_error
515			`s` contains an invalid percent-encoding.
516
517			@param s The string to set.
518
519			@par BNF
520			@code
521			userinfo = [ [ user ] [ ':' password ] ]
522
523			user = *( unreserved / pct-encoded / sub-delims )
524			password = *( unreserved / pct-encoded / sub-delims / ":" )
525			@endcode
526
527			@par Specification
528			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.1">
529			3.2.1. User Information (rfc3986)</a>
530
531			@see
532			@ref remove_userinfo,
533			@ref set_userinfo.
534			*/
535			url_base&
536			set_encoded_userinfo(
537			pct_string_view s);
538
539			/** Remove the userinfo
540
541			This function removes the userinfo if
542			present, without removing any authority.
543
544			@par Example
545			@code
546			assert( url( "http://user@example.com" ).remove_userinfo().has_userinfo() == false );
547			@endcode
548
549			@par Postconditions
550			@code
551			this->has_userinfo() == false && this->encoded_userinfo().empty == true
552			@endcode
553
554			@par Complexity
555			Linear in `this->size()`.
556
557			@par Exception Safety
558			Throws nothing.
559
560			@par BNF
561			@code
562			userinfo = [ [ user ] [ ':' password ] ]
563
564			user = *( unreserved / pct-encoded / sub-delims )
565			password = *( unreserved / pct-encoded / sub-delims / ":" )
566			@endcode
567
568			@par Specification
569			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.1">
570			3.2.1. User Information (rfc3986)</a>
571
572			@see
573			@ref set_encoded_userinfo,
574			@ref set_userinfo.
575			*/
576			url_base&
577			remove_userinfo() noexcept;
578
579			//--------------------------------------------
580
581			/** Set the user
582
583			This function sets the user part of the
584			userinfo to the string.
585			Any special or reserved characters in the
586			string are automatically percent-encoded.
587
588			@par Example
589			@code
590			assert( url().set_user("john doe").encoded_userinfo() == "john%20doe" );
591			@endcode
592
593			@par Postconditions
594			@code
595			this->has_authority() == true && this->has_userinfo() == true
596			@endcode
597
598			@par Complexity
599			Linear in `this->size() + s.size()`.
600
601			@par Exception Safety
602			Strong guarantee.
603			Calls to allocate may throw.
604
605			@param s The string to set.
606
607			@par BNF
608			@code
609			userinfo = [ [ user ] [ ':' password ] ]
610
611			user = *( unreserved / pct-encoded / sub-delims )
612			password = *( unreserved / pct-encoded / sub-delims / ":" )
613			@endcode
614
615			@par Specification
616			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.1">
617			3.2.1. User Information (rfc3986)</a>
618
619			@see
620			@ref remove_password,
621			@ref set_encoded_password,
622			@ref set_encoded_user,
623			@ref set_password.
624			*/
625			url_base&
626			set_user(
627			core::string_view s);
628
629			/** Set the user
630
631			This function sets the user part of the
632			userinfo the the string, which may
633			contain percent-escapes.
634			Escapes in the string are preserved,
635			and reserved characters in the string
636			are percent-escaped in the result.
637
638			@par Example
639			@code
640			assert( url().set_encoded_user("john%20doe").userinfo() == "john doe" );
641			@endcode
642
643			@par Postconditions
644			@code
645			this->has_authority() == true && this->has_userinfo() == true
646			@endcode
647
648			@par Complexity
649			Linear in `this->size() + s.size()`.
650
651			@par Exception Safety
652			Strong guarantee.
653			Calls to allocate may throw.
654
655			@throw system_error
656			`s` contains an invalid percent-encoding.
657
658			@param s The string to set.
659
660			@par BNF
661			@code
662			userinfo = [ [ user ] [ ':' password ] ]
663
664			user = *( unreserved / pct-encoded / sub-delims )
665			password = *( unreserved / pct-encoded / sub-delims / ":" )
666			@endcode
667
668			@par Specification
669			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.1">
670			3.2.1. User Information (rfc3986)</a>
671
672			@see
673			@ref remove_password,
674			@ref set_encoded_password,
675			@ref set_password,
676			@ref set_user.
677			*/
678			url_base&
679			set_encoded_user(
680			pct_string_view s);
681
682			/** Set the password.
683
684			This function sets the password in
685			the userinfo to the string.
686			Reserved characters in the string are
687			percent-escaped in the result.
688
689			@note
690			The interpretation of the userinfo as
691			individual user and password components
692			is scheme-dependent. Transmitting
693			passwords in URLs is deprecated.
694
695			@par Example
696			@code
697			assert( url("http://user@example.com").set_password( "pass" ).encoded_userinfo() == "user:pass" );
698			@endcode
699
700			@par Postconditions
701			@code
702			this->has_password() == true && this->password() == s
703			@endcode
704
705			@par Exception Safety
706			Strong guarantee.
707			Calls to allocate may throw.
708
709			@param s The string to set. This string may
710			contain any characters, including nulls.
711
712			@par BNF
713			@code
714			userinfo = [ [ user ] [ ':' password ] ]
715
716			user = *( unreserved / pct-encoded / sub-delims )
717			password = *( unreserved / pct-encoded / sub-delims / ":" )
718			@endcode
719
720			@par Specification
721			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.1">
722			3.2.1. User Information (rfc3986)</a>
723
724			@see
725			@ref remove_password,
726			@ref set_encoded_password,
727			@ref set_encoded_user,
728			@ref set_user.
729			*/
730			url_base&
731			set_password(
732			core::string_view s);
733
734			/** Set the password.
735
736			This function sets the password in
737			the userinfo to the string, which
738			may contain percent-escapes.
739			Escapes in the string are preserved,
740			and reserved characters in the string
741			are percent-escaped in the result.
742
743			@note
744			The interpretation of the userinfo as
745			individual user and password components
746			is scheme-dependent. Transmitting
747			passwords in URLs is deprecated.
748
749			@par Example
750			@code
751			assert( url("http://user@example.com").set_encoded_password( "pass" ).encoded_userinfo() == "user:pass" );
752			@endcode
753
754			@par Postconditions
755			@code
756			this->has_password() == true
757			@endcode
758
759			@par Exception Safety
760			Strong guarantee.
761			Calls to allocate may throw.
762
763			@throw system_error
764			`s` contains an invalid percent-encoding.
765
766			@param s The string to set. This string may
767			contain any characters, including nulls.
768
769			@par BNF
770			@code
771			userinfo = [ [ user ] [ ':' password ] ]
772
773			user = *( unreserved / pct-encoded / sub-delims )
774			password = *( unreserved / pct-encoded / sub-delims / ":" )
775			@endcode
776
777			@par Specification
778			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.1">
779			3.2.1. User Information (rfc3986)</a>
780
781			@see
782			@ref remove_password,
783			@ref set_encoded_password,
784			@ref set_encoded_user,
785			@ref set_user.
786			*/
787			url_base&
788			set_encoded_password(
789			pct_string_view s);
790
791			/** Remove the password
792
793			This function removes the password from
794			the userinfo if a password exists. If
795			there is no userinfo or no authority,
796			the call has no effect.
797
798			@note
799			The interpretation of the userinfo as
800			individual user and password components
801			is scheme-dependent. Transmitting
802			passwords in URLs is deprecated.
803
804			@par Example
805			@code
806			assert( url( "http://user:pass@example.com" ).remove_password().authority().buffer() == "user@example.com" );
807			@endcode
808
809			@par Postconditions
810			@code
811			this->has_password() == false && this->encoded_password().empty() == true
812			@endcode
813
814			@par Complexity
815			Linear in `this->size()`.
816
817			@par Exception Safety
818			Throws nothing.
819
820			@par BNF
821			@code
822			userinfo = [ [ user ] [ ':' password ] ]
823
824			user = *( unreserved / pct-encoded / sub-delims )
825			password = *( unreserved / pct-encoded / sub-delims / ":" )
826			@endcode
827
828			@par Specification
829			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.1">
830			3.2.1. User Information (rfc3986)</a>
831
832			@see
833			@ref set_encoded_password,
834			@ref set_encoded_user,
835			@ref set_password,
836			@ref set_user.
837			*/
838			url_base&
839			remove_password() noexcept;
840
841			//--------------------------------------------
842			//
843			// Host
844			//
845			//--------------------------------------------
846
847			/** Set the host
848
849			Depending on the contents of the passed
850			string, this function sets the host:
851
852			@li If the string is a valid IPv4 address,
853			then the host is set to the address.
854			The host type is @ref host_type::ipv4.
855
856			@li If the string is a valid IPv6 address
857			enclosed in square brackets, then the
858			host is set to that address.
859			The host type is @ref host_type::ipv6.
860
861			@li If the string is a valid IPvFuture
862			address enclosed in square brackets, then
863			the host is set to that address.
864			The host type is @ref host_type::ipvfuture.
865
866			@li Otherwise, the host name is set to
867			the string, which may be empty.
868			Reserved characters in the string are
869			percent-escaped in the result.
870			The host type is @ref host_type::name.
871
872			In all cases, when this function returns,
873			the URL contains an authority.
874
875			@par Example
876			@code
877			assert( url( "http://www.example.com" ).set_host( "127.0.0.1" ).buffer() == "http://127.0.0.1" );
878			@endcode
879
880			@par Postconditions
881			@code
882			this->has_authority() == true
883			@endcode
884
885			@par Complexity
886			Linear in `this->size() + s.size()`.
887
888			@par Exception Safety
889			Strong guarantee.
890			Calls to allocate may throw.
891
892			@param s The string to set.
893
894			@par BNF
895			@code
896			host = IP-literal / IPv4address / reg-name
897
898			IP-literal = "[" ( IPv6address / IPvFuture ) "]"
899
900			reg-name = *( unreserved / pct-encoded / "-" / ".")
901			@endcode
902
903			@par Specification
904			@li <a href="https://en.wikipedia.org/wiki/IPv4"
905			>IPv4 (Wikipedia)</a>
906			@li <a href="https://datatracker.ietf.org/doc/html/rfc4291"
907			>IP Version 6 Addressing Architecture (rfc4291)</a>
908			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.2">
909			3.2.2. Host (rfc3986)</a>
910
911			@see
912			@ref set_encoded_host,
913			@ref set_encoded_host_address,
914			@ref set_encoded_host_name,
915			@ref set_host_address,
916			@ref set_host_ipv4,
917			@ref set_host_ipv6,
918			@ref set_host_ipvfuture,
919			@ref set_host_name.
920			*/
921			url_base&
922			set_host(
923			core::string_view s);
924
925			/** Set the host
926
927			Depending on the contents of the passed
928			string, this function sets the host:
929
930			@li If the string is a valid IPv4 address,
931			then the host is set to the address.
932			The host type is @ref host_type::ipv4.
933
934			@li If the string is a valid IPv6 address
935			enclosed in square brackets, then the
936			host is set to that address.
937			The host type is @ref host_type::ipv6.
938
939			@li If the string is a valid IPvFuture
940			address enclosed in square brackets, then
941			the host is set to that address.
942			The host type is @ref host_type::ipvfuture.
943
944			@li Otherwise, the host name is set to
945			the string. This string can contain percent
946			escapes, or can be empty.
947			Escapes in the string are preserved,
948			and reserved characters in the string
949			are percent-escaped in the result.
950			The host type is @ref host_type::name.
951
952			In all cases, when this function returns,
953			the URL contains an authority.
954
955			@par Example
956			@code
957			assert( url( "http://www.example.com" ).set_host( "127.0.0.1" ).buffer() == "http://127.0.0.1" );
958			@endcode
959
960			@par Postconditions
961			@code
962			this->has_authority() == true
963			@endcode
964
965			@par Complexity
966			Linear in `this->size() + s.size()`.
967
968			@par Exception Safety
969			Strong guarantee.
970			Calls to allocate may throw.
971			Exceptions thrown on invalid input.
972
973			@throw system_error
974			`s` contains an invalid percent-encoding.
975
976			@param s The string to set.
977
978			@par BNF
979			@code
980			host = IP-literal / IPv4address / reg-name
981
982			IP-literal = "[" ( IPv6address / IPvFuture ) "]"
983
984			reg-name = *( unreserved / pct-encoded / "-" / ".")
985			@endcode
986
987			@par Specification
988			@li <a href="https://en.wikipedia.org/wiki/IPv4"
989			>IPv4 (Wikipedia)</a>
990			@li <a href="https://datatracker.ietf.org/doc/html/rfc4291"
991			>IP Version 6 Addressing Architecture (rfc4291)</a>
992			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.2">
993			3.2.2. Host (rfc3986)</a>
994
995			@see
996			@ref set_encoded_host_address,
997			@ref set_encoded_host_name,
998			@ref set_host,
999			@ref set_host_address,
1000			@ref set_host_ipv4,
1001			@ref set_host_ipv6,
1002			@ref set_host_ipvfuture,
1003			@ref set_host_name.
1004			*/
1005			url_base&
1006			set_encoded_host(pct_string_view s);
1007
1008			/** Set the host to an address
1009
1010			Depending on the contents of the passed
1011			string, this function sets the host:
1012
1013			@li If the string is a valid IPv4 address,
1014			then the host is set to the address.
1015			The host type is @ref host_type::ipv4.
1016
1017			@li If the string is a valid IPv6 address,
1018			then the host is set to that address.
1019			The host type is @ref host_type::ipv6.
1020
1021			@li If the string is a valid IPvFuture,
1022			then the host is set to that address.
1023			The host type is @ref host_type::ipvfuture.
1024
1025			@li Otherwise, the host name is set to
1026			the string, which may be empty.
1027			Reserved characters in the string are
1028			percent-escaped in the result.
1029			The host type is @ref host_type::name.
1030
1031			In all cases, when this function returns,
1032			the URL contains an authority.
1033
1034			@par Example
1035			@code
1036			assert( url( "http://www.example.com" ).set_host_address( "127.0.0.1" ).buffer() == "http://127.0.0.1" );
1037			@endcode
1038
1039			@par Postconditions
1040			@code
1041			this->has_authority() == true
1042			@endcode
1043
1044			@par Complexity
1045			Linear in `s.size()`.
1046
1047			@par Exception Safety
1048			Strong guarantee.
1049			Calls to allocate may throw.
1050
1051			@param s The string to set.
1052
1053			@par BNF
1054			@code
1055			IPv4address = dec-octet "." dec-octet "." dec-octet "." dec-octet
1056
1057			dec-octet = DIGIT ; 0-9
1058			/ %x31-39 DIGIT ; 10-99
1059			/ "1" 2DIGIT ; 100-199
1060			/ "2" %x30-34 DIGIT ; 200-249
1061			/ "25" %x30-35 ; 250-255
1062
1063			IPv6address = 6( h16 ":" ) ls32
1064			/ "::" 5( h16 ":" ) ls32
1065			/ [ h16 ] "::" 4( h16 ":" ) ls32
1066			/ [ *1( h16 ":" ) h16 ] "::" 3( h16 ":" ) ls32
1067			/ [ *2( h16 ":" ) h16 ] "::" 2( h16 ":" ) ls32
1068			/ [ *3( h16 ":" ) h16 ] "::" h16 ":" ls32
1069			/ [ *4( h16 ":" ) h16 ] "::" ls32
1070			/ [ *5( h16 ":" ) h16 ] "::" h16
1071			/ [ *6( h16 ":" ) h16 ] "::"
1072
1073			ls32 = ( h16 ":" h16 ) / IPv4address
1074			; least-significant 32 bits of address
1075
1076			h16 = 1*4HEXDIG
1077			; 16 bits of address represented in hexadecimal
1078
1079			IPvFuture = "v" 1*HEXDIG "." 1*( unreserved / sub-delims / ":" )
1080
1081			reg-name = *( unreserved / pct-encoded / "-" / ".")
1082			@endcode
1083
1084			@par Specification
1085			@li <a href="https://en.wikipedia.org/wiki/IPv4"
1086			>IPv4 (Wikipedia)</a>
1087			@li <a href="https://datatracker.ietf.org/doc/html/rfc4291"
1088			>IP Version 6 Addressing Architecture (rfc4291)</a>
1089			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.2">
1090			3.2.2. Host (rfc3986)</a>
1091
1092			@see
1093			@ref set_encoded_host,
1094			@ref set_encoded_host_address,
1095			@ref set_encoded_host_name,
1096			@ref set_host,
1097			@ref set_host_address,
1098			@ref set_host_ipv4,
1099			@ref set_host_ipv6,
1100			@ref set_host_ipvfuture,
1101			@ref set_host_name.
1102			*/
1103			url_base&
1104			set_host_address(core::string_view s);
1105
1106			/** Set the host to an address
1107
1108			Depending on the contents of the passed
1109			string, this function sets the host:
1110
1111			@li If the string is a valid IPv4 address,
1112			then the host is set to the address.
1113			The host type is @ref host_type::ipv4.
1114
1115			@li If the string is a valid IPv6 address,
1116			then the host is set to that address.
1117			The host type is @ref host_type::ipv6.
1118
1119			@li If the string is a valid IPvFuture,
1120			then the host is set to that address.
1121			The host type is @ref host_type::ipvfuture.
1122
1123			@li Otherwise, the host name is set to
1124			the string. This string can contain percent
1125			escapes, or can be empty.
1126			Escapes in the string are preserved,
1127			and reserved characters in the string
1128			are percent-escaped in the result.
1129			The host type is @ref host_type::name.
1130
1131			In all cases, when this function returns,
1132			the URL contains an authority.
1133
1134			@par Example
1135			@code
1136			assert( url( "http://www.example.com" ).set_host( "127.0.0.1" ).buffer() == "http://127.0.0.1" );
1137			@endcode
1138
1139			@par Postconditions
1140			@code
1141			this->has_authority() == true
1142			@endcode
1143
1144			@par Complexity
1145			Linear in `this->size() + s.size()`.
1146
1147			@par Exception Safety
1148			Strong guarantee.
1149			Calls to allocate may throw.
1150			Exceptions thrown on invalid input.
1151
1152			@throw system_error
1153			`s` contains an invalid percent-encoding.
1154
1155			@param s The string to set.
1156
1157			@par BNF
1158			@code
1159			IPv4address = dec-octet "." dec-octet "." dec-octet "." dec-octet
1160
1161			dec-octet = DIGIT ; 0-9
1162			/ %x31-39 DIGIT ; 10-99
1163			/ "1" 2DIGIT ; 100-199
1164			/ "2" %x30-34 DIGIT ; 200-249
1165			/ "25" %x30-35 ; 250-255
1166
1167			IPv6address = 6( h16 ":" ) ls32
1168			/ "::" 5( h16 ":" ) ls32
1169			/ [ h16 ] "::" 4( h16 ":" ) ls32
1170			/ [ *1( h16 ":" ) h16 ] "::" 3( h16 ":" ) ls32
1171			/ [ *2( h16 ":" ) h16 ] "::" 2( h16 ":" ) ls32
1172			/ [ *3( h16 ":" ) h16 ] "::" h16 ":" ls32
1173			/ [ *4( h16 ":" ) h16 ] "::" ls32
1174			/ [ *5( h16 ":" ) h16 ] "::" h16
1175			/ [ *6( h16 ":" ) h16 ] "::"
1176
1177			ls32 = ( h16 ":" h16 ) / IPv4address
1178			; least-significant 32 bits of address
1179
1180			h16 = 1*4HEXDIG
1181			; 16 bits of address represented in hexadecimal
1182
1183			IPvFuture = "v" 1*HEXDIG "." 1*( unreserved / sub-delims / ":" )
1184
1185			reg-name = *( unreserved / pct-encoded / "-" / ".")
1186			@endcode
1187
1188			@par Specification
1189			@li <a href="https://en.wikipedia.org/wiki/IPv4"
1190			>IPv4 (Wikipedia)</a>
1191			@li <a href="https://datatracker.ietf.org/doc/html/rfc4291"
1192			>IP Version 6 Addressing Architecture (rfc4291)</a>
1193			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.2">
1194			3.2.2. Host (rfc3986)</a>
1195
1196			@see
1197			@ref set_encoded_host,
1198			@ref set_encoded_host_name,
1199			@ref set_host,
1200			@ref set_host_address,
1201			@ref set_host_ipv4,
1202			@ref set_host_ipv6,
1203			@ref set_host_ipvfuture,
1204			@ref set_host_name.
1205			*/
1206			url_base&
1207			set_encoded_host_address(
1208			pct_string_view s);
1209
1210			/** Set the host to an address
1211
1212			The host is set to the specified IPv4
1213			address.
1214			The host type is @ref host_type::ipv4.
1215
1216			@par Example
1217			@code
1218			assert( url("http://www.example.com").set_host_ipv4( ipv4_address( "127.0.0.1" ) ).buffer() == "http://127.0.0.1" );
1219			@endcode
1220
1221			@par Complexity
1222			Linear in `this->size()`.
1223
1224			@par Postconditions
1225			@code
1226			this->has_authority() == true && this->host_ipv4_address() == addr && this->host_type() == host_type::ipv4
1227			@endcode
1228
1229			@par Exception Safety
1230			Strong guarantee.
1231			Calls to allocate may throw.
1232
1233			@param addr The address to set.
1234
1235			@par BNF
1236			@code
1237			IPv4address = dec-octet "." dec-octet "." dec-octet "." dec-octet
1238
1239			dec-octet = DIGIT ; 0-9
1240			/ %x31-39 DIGIT ; 10-99
1241			/ "1" 2DIGIT ; 100-199
1242			/ "2" %x30-34 DIGIT ; 200-249
1243			/ "25" %x30-35 ; 250-255
1244			@endcode
1245
1246			@par Specification
1247			@li <a href="https://en.wikipedia.org/wiki/IPv4"
1248			>IPv4 (Wikipedia)</a>
1249			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.2">
1250			3.2.2. Host (rfc3986)</a>
1251
1252			@see
1253			@ref set_encoded_host,
1254			@ref set_encoded_host_address,
1255			@ref set_encoded_host_name,
1256			@ref set_host,
1257			@ref set_host_address,
1258			@ref set_host_ipv6,
1259			@ref set_host_ipvfuture,
1260			@ref set_host_name.
1261			*/
1262			url_base&
1263			set_host_ipv4(
1264			ipv4_address const& addr);
1265
1266			/** Set the host to an address
1267
1268			The host is set to the specified IPv6
1269			address.
1270			The host type is @ref host_type::ipv6.
1271
1272			@par Example
1273			@code
1274			assert( url().set_host_ipv6( ipv6_address( "1::6:c0a8:1" ) ).authority().buffer() == "[1::6:c0a8:1]" );
1275			@endcode
1276
1277			@par Postconditions
1278			@code
1279			this->has_authority() == true && this->host_ipv6_address() == addr && this->host_type() == host_type::ipv6
1280			@endcode
1281
1282			@par Complexity
1283			Linear in `this->size()`.
1284
1285			@par Exception Safety
1286			Strong guarantee.
1287			Calls to allocate may throw.
1288
1289			@param addr The address to set.
1290
1291			@par BNF
1292			@code
1293			IPv6address = 6( h16 ":" ) ls32
1294			/ "::" 5( h16 ":" ) ls32
1295			/ [ h16 ] "::" 4( h16 ":" ) ls32
1296			/ [ *1( h16 ":" ) h16 ] "::" 3( h16 ":" ) ls32
1297			/ [ *2( h16 ":" ) h16 ] "::" 2( h16 ":" ) ls32
1298			/ [ *3( h16 ":" ) h16 ] "::" h16 ":" ls32
1299			/ [ *4( h16 ":" ) h16 ] "::" ls32
1300			/ [ *5( h16 ":" ) h16 ] "::" h16
1301			/ [ *6( h16 ":" ) h16 ] "::"
1302
1303			ls32 = ( h16 ":" h16 ) / IPv4address
1304			; least-significant 32 bits of address
1305
1306			h16 = 1*4HEXDIG
1307			; 16 bits of address represented in hexadecimal
1308			@endcode
1309
1310			@par Specification
1311			@li <a href="https://datatracker.ietf.org/doc/html/rfc4291"
1312			>IP Version 6 Addressing Architecture (rfc4291)</a>
1313			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.2">
1314			3.2.2. Host (rfc3986)</a>
1315
1316			@see
1317			@ref set_encoded_host,
1318			@ref set_encoded_host_address,
1319			@ref set_encoded_host_name,
1320			@ref set_host,
1321			@ref set_host_address,
1322			@ref set_host_ipv4,
1323			@ref set_host_ipvfuture,
1324			@ref set_host_name.
1325			*/
1326			url_base&
1327			set_host_ipv6(
1328			ipv6_address const& addr);
1329
1330			/** Set the host to an address
1331
1332			The host is set to the specified IPvFuture
1333			string.
1334			The host type is @ref host_type::ipvfuture.
1335
1336			@par Example
1337			@code
1338			assert( url().set_host_ipvfuture( "v42.bis" ).buffer() == "//[v42.bis]" );
1339			@endcode
1340
1341			@par Complexity
1342			Linear in `this->size() + s.size()`.
1343
1344			@par Postconditions
1345			@code
1346			this->has_authority() == true && this->host_ipvfuture) == s && this->host_type() == host_type::ipvfuture
1347			@endcode
1348
1349			@par Exception Safety
1350			Strong guarantee.
1351			Calls to allocate may throw.
1352			Exceptions thrown on invalid input.
1353
1354			@throw system_error
1355			`s` contains an invalid percent-encoding.
1356
1357			@param s The string to set.
1358
1359			@par BNF
1360			@code
1361			IPvFuture = "v" 1*HEXDIG "." 1*( unreserved / sub-delims / ":" )
1362			@endcode
1363
1364			@par Specification
1365			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.2">
1366			3.2.2. Host (rfc3986)</a>
1367
1368			@see
1369			@ref set_encoded_host,
1370			@ref set_encoded_host_address,
1371			@ref set_encoded_host_name,
1372			@ref set_host,
1373			@ref set_host_address,
1374			@ref set_host_ipv4,
1375			@ref set_host_ipv6,
1376			@ref set_host_name.
1377			*/
1378			url_base&
1379			set_host_ipvfuture(
1380			core::string_view s);
1381
1382			/** Set the host to a name
1383
1384			The host is set to the specified string,
1385			which may be empty.
1386			Reserved characters in the string are
1387			percent-escaped in the result.
1388			The host type is @ref host_type::name.
1389
1390			@par Example
1391			@code
1392			assert( url( "http://www.example.com/index.htm").set_host_name( "localhost" ).host_address() == "localhost" );
1393			@endcode
1394
1395			@par Postconditions
1396			@code
1397			this->has_authority() == true && this->host_ipv6_address() == addr && this->host_type() == host_type::name
1398			@endcode
1399
1400			@par Exception Safety
1401			Strong guarantee.
1402			Calls to allocate may throw.
1403
1404			@param s The string to set.
1405
1406			@par BNF
1407			@code
1408			reg-name = *( unreserved / pct-encoded / "-" / ".")
1409			@endcode
1410
1411			@par Specification
1412			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.2">
1413			3.2.2. Host (rfc3986)</a>
1414
1415			@see
1416			@ref set_encoded_host,
1417			@ref set_encoded_host_address,
1418			@ref set_encoded_host_name,
1419			@ref set_host,
1420			@ref set_host_address,
1421			@ref set_host_ipv4,
1422			@ref set_host_ipv6,
1423			@ref set_host_ipvfuture.
1424			*/
1425			url_base&
1426			set_host_name(
1427			core::string_view s);
1428
1429			/** Set the host to a name
1430
1431			The host is set to the specified string,
1432			which may contain percent-escapes and
1433			can be empty.
1434			Escapes in the string are preserved,
1435			and reserved characters in the string
1436			are percent-escaped in the result.
1437			The host type is @ref host_type::name.
1438
1439			@par Example
1440			@code
1441			assert( url( "http://www.example.com/index.htm").set_encoded_host_name( "localhost" ).host_address() == "localhost" );
1442			@endcode
1443
1444			@par Postconditions
1445			@code
1446			this->has_authority() == true && this->host_ipv6_address() == addr && this->host_type() == host_type::name
1447			@endcode
1448
1449			@par Exception Safety
1450			Strong guarantee.
1451			Calls to allocate may throw.
1452			Exceptions thrown on invalid input.
1453
1454			@throw system_error
1455			`s` contains an invalid percent-encoding.
1456
1457			@param s The string to set.
1458
1459			@par BNF
1460			@code
1461			reg-name = *( unreserved / pct-encoded / "-" / ".")
1462			@endcode
1463
1464			@par Specification
1465			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.2">
1466			3.2.2. Host (rfc3986)</a>
1467
1468			@see
1469			@ref set_encoded_host,
1470			@ref set_encoded_host_address,
1471			@ref set_host,
1472			@ref set_host_address,
1473			@ref set_host_ipv4,
1474			@ref set_host_ipv6,
1475			@ref set_host_ipvfuture,
1476			@ref set_host_name.
1477			*/
1478			url_base&
1479			set_encoded_host_name(
1480			pct_string_view s);
1481
1482			//--------------------------------------------
1483
1484			/** Set the port
1485
1486			The port is set to the specified integer.
1487
1488			@par Example
1489			@code
1490			assert( url( "http://www.example.com" ).set_port_number( 8080 ).authority().buffer() == "www.example.com:8080" );
1491			@endcode
1492
1493			@par Postconditions
1494			@code
1495			this->has_authority() == true && this->has_port() == true && this->port_number() == n
1496			@endcode
1497
1498			@par Complexity
1499			Linear in `this->size()`.
1500
1501			@par Exception Safety
1502			Strong guarantee.
1503			Calls to allocate may throw.
1504
1505			@param n The port number to set.
1506
1507			@par BNF
1508			@code
1509			authority = [ userinfo "@" ] host [ ":" port ]
1510
1511			port = *DIGIT
1512			@endcode
1513
1514			@par Specification
1515			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.3">
1516			3.2.3. Port (rfc3986)</a>
1517
1518			@see
1519			@ref remove_port,
1520			@ref set_port.
1521			*/
1522			url_base&
1523			set_port_number(std::uint16_t n);
1524
1525			/** Set the port
1526
1527			This port is set to the string, which
1528			must contain only digits or be empty.
1529			An empty port string is distinct from
1530			having no port.
1531
1532			@par Example
1533			@code
1534			assert( url( "http://www.example.com" ).set_port( "8080" ).authority().buffer() == "www.example.com:8080" );
1535			@endcode
1536
1537			@par Postconditions
1538			@code
1539			this->has_port() == true && this->port_number() == n && this->port() == std::to_string(n)
1540			@endcode
1541
1542			@par Exception Safety
1543			Strong guarantee.
1544			Calls to allocate may throw.
1545			Exceptions thrown on invalid input.
1546
1547			@throw system_error
1548			`s` does not contain a valid port.
1549
1550			@param s The port string to set.
1551
1552			@par BNF
1553			@code
1554			port = *DIGIT
1555			@endcode
1556
1557			@par Specification
1558			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.3">
1559			3.2.3. Port (rfc3986)</a>
1560
1561			@see
1562			@ref remove_port,
1563			@ref set_port.
1564			*/
1565			url_base&
1566			set_port(core::string_view s);
1567
1568			/** Remove the port
1569
1570			If a port exists, it is removed. The rest
1571			of the authority is unchanged.
1572
1573			@par Example
1574			@code
1575			assert( url( "http://www.example.com:80" ).remove_port().authority().buffer() == "www.example.com" );
1576			@endcode
1577
1578			@par Postconditions
1579			@code
1580			this->has_port() == false && this->port_number() == 0 && this->port() == ""
1581			@endcode
1582
1583			@par Complexity
1584			Linear in `this->size()`.
1585
1586			@par Exception Safety
1587			Throws nothing.
1588
1589			@par BNF
1590			@code
1591			authority = [ userinfo "@" ] host [ ":" port ]
1592
1593			port = *DIGIT
1594			@endcode
1595
1596			@par Specification
1597			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.3">
1598			3.2.3. Port (rfc3986)</a>
1599
1600			@see
1601			@ref set_port.
1602			*/
1603			url_base&
1604			remove_port() noexcept;
1605
1606			//--------------------------------------------
1607			//
1608			// Path
1609			//
1610			//--------------------------------------------
1611
1612			/** Set if the path is absolute
1613
1614			This function adjusts the path to make
1615			it absolute or not, depending on the
1616			parameter.
1617
1618			@note
1619			If an authority is present, the path
1620			is always absolute. In this case, the
1621			function has no effect.
1622
1623			@par Example
1624			@code
1625			url u( "path/to/file.txt" );
1626			assert( u.set_path_absolute( true ) );
1627			assert( u.buffer() == "/path/to/file.txt" );
1628			@endcode
1629
1630			@par Postconditions
1631			@code
1632			this->is_path_absolute() == true && this->encoded_path().front() == '/'
1633			@endcode
1634
1635			@return true on success.
1636
1637			@par Complexity
1638			Linear in `this->size()`.
1639
1640			@par BNF
1641			@code
1642			path = path-abempty ; begins with "/" or is empty
1643			/ path-absolute ; begins with "/" but not "//"
1644			/ path-noscheme ; begins with a non-colon segment
1645			/ path-rootless ; begins with a segment
1646			/ path-empty ; zero characters
1647
1648			path-abempty = *( "/" segment )
1649			path-absolute = "/" [ segment-nz *( "/" segment ) ]
1650			path-noscheme = segment-nz-nc *( "/" segment )
1651			path-rootless = segment-nz *( "/" segment )
1652			path-empty = 0<pchar>
1653			@endcode
1654
1655			@par Specification
1656			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.3"
1657			>3.3. Path (rfc3986)</a>
1658
1659			@see
1660			@ref encoded_segments,
1661			@ref segments,
1662			@ref set_encoded_path,
1663			@ref set_path.
1664			*/
1665			bool
1666			set_path_absolute(bool absolute);
1667
1668			/** Set the path.
1669
1670			This function sets the path to the
1671			string, which may be empty.
1672			Reserved characters in the string are
1673			percent-escaped in the result.
1674
1675			@note
1676			The library may adjust the final result
1677			to ensure that no other parts of the url
1678			is semantically affected.
1679
1680			@note
1681			This function does not encode '/' chars, which
1682			are unreserved for paths but reserved for
1683			path segments. If a path segment should include
1684			encoded '/'s to differentiate it from path separators,
1685			the functions @ref set_encoded_path or @ref segments
1686			should be used instead.
1687
1688			@par Example
1689			@code
1690			url u( "http://www.example.com" );
1691
1692			u.set_path( "path/to/file.txt" );
1693
1694			assert( u.path() == "/path/to/file.txt" );
1695			@endcode
1696
1697			@par Complexity
1698			Linear in `this->size() + s.size()`.
1699
1700			@par Exception Safety
1701			Strong guarantee.
1702			Calls to allocate may throw.
1703
1704			@param s The string to set.
1705
1706			@par BNF
1707			@code
1708			path = path-abempty ; begins with "/" or is empty
1709			/ path-absolute ; begins with "/" but not "//"
1710			/ path-noscheme ; begins with a non-colon segment
1711			/ path-rootless ; begins with a segment
1712			/ path-empty ; zero characters
1713
1714			path-abempty = *( "/" segment )
1715			path-absolute = "/" [ segment-nz *( "/" segment ) ]
1716			path-noscheme = segment-nz-nc *( "/" segment )
1717			path-rootless = segment-nz *( "/" segment )
1718			path-empty = 0<pchar>
1719			@endcode
1720
1721			@par Specification
1722			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.3"
1723			>3.3. Path (rfc3986)</a>
1724
1725			@see
1726			@ref encoded_segments,
1727			@ref segments,
1728			@ref set_encoded_path,
1729			@ref set_path_absolute.
1730			*/
1731			url_base&
1732			set_path(
1733			core::string_view s);
1734
1735			/** Set the path.
1736
1737			This function sets the path to the
1738			string, which may contain percent-escapes
1739			and can be empty.
1740			Escapes in the string are preserved,
1741			and reserved characters in the string
1742			are percent-escaped in the result.
1743
1744			@note
1745			The library may adjust the final result
1746			to ensure that no other parts of the url
1747			is semantically affected.
1748
1749			@par Example
1750			@code
1751			url u( "http://www.example.com" );
1752
1753			u.set_encoded_path( "path/to/file.txt" );
1754
1755			assert( u.encoded_path() == "/path/to/file.txt" );
1756			@endcode
1757
1758			@par Complexity
1759			Linear in `this->size() + s.size()`.
1760
1761			@par Exception Safety
1762			Strong guarantee.
1763			Calls to allocate may throw.
1764			Exceptions thrown on invalid input.
1765
1766			@throw system_error
1767			`s` contains an invalid percent-encoding.
1768
1769			@param s The string to set.
1770
1771			@par BNF
1772			@code
1773			path = path-abempty ; begins with "/" or is empty
1774			/ path-absolute ; begins with "/" but not "//"
1775			/ path-noscheme ; begins with a non-colon segment
1776			/ path-rootless ; begins with a segment
1777			/ path-empty ; zero characters
1778
1779			path-abempty = *( "/" segment )
1780			path-absolute = "/" [ segment-nz *( "/" segment ) ]
1781			path-noscheme = segment-nz-nc *( "/" segment )
1782			path-rootless = segment-nz *( "/" segment )
1783			path-empty = 0<pchar>
1784			@endcode
1785
1786			@par Specification
1787			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.3"
1788			>3.3. Path (rfc3986)</a>
1789
1790			@see
1791			@ref encoded_segments,
1792			@ref segments,
1793			@ref set_path,
1794			@ref set_path_absolute.
1795			*/
1796			url_base&
1797			set_encoded_path(
1798			pct_string_view s);
1799
1800			/** Return the path as a container of segments
1801
1802			This function returns a bidirectional
1803			view of segments over the path.
1804			The returned view references the same
1805			underlying character buffer; ownership
1806			is not transferred.
1807			Any percent-escapes in strings returned
1808			when iterating the view are decoded first.
1809			The container is modifiable; changes
1810			to the container are reflected in the
1811			underlying URL.
1812
1813			@par Example
1814			@code
1815			url u( "http://example.com/path/to/file.txt" );
1816
1817			segments sv = u.segments();
1818			@endcode
1819
1820			@par Complexity
1821			Constant.
1822
1823			@par Exception Safety
1824			Throws nothing.
1825
1826			@par BNF
1827			@code
1828			path = path-abempty ; begins with "/" or is empty
1829			/ path-absolute ; begins with "/" but not "//"
1830			/ path-noscheme ; begins with a non-colon segment
1831			/ path-rootless ; begins with a segment
1832			/ path-empty ; zero characters
1833
1834			path-abempty = *( "/" segment )
1835			path-absolute = "/" [ segment-nz *( "/" segment ) ]
1836			path-noscheme = segment-nz-nc *( "/" segment )
1837			path-rootless = segment-nz *( "/" segment )
1838			path-empty = 0<pchar>
1839			@endcode
1840
1841			@par Specification
1842			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.3"
1843			>3.3. Path (rfc3986)</a>
1844
1845			@see
1846			@ref encoded_segments,
1847			@ref set_encoded_path,
1848			@ref set_path,
1849			@ref set_path_absolute.
1850			*/
1851			urls::segments_ref
1852			segments() noexcept;
1853
1854			/// @copydoc url_view_base::segments
1855			segments_view
1856		1	segments() const noexcept
1857			{
1858		1	return url_view_base::segments();
1859			}
1860
1861			/** Return the path as a container of segments
1862
1863			This function returns a bidirectional
1864			view of segments over the path.
1865			The returned view references the same
1866			underlying character buffer; ownership
1867			is not transferred.
1868			Strings returned when iterating the
1869			range may contain percent escapes.
1870			The container is modifiable; changes
1871			to the container are reflected in the
1872			underlying URL.
1873
1874			@par Example
1875			@code
1876			url u( "http://example.com/path/to/file.txt" );
1877
1878			segments_encoded_ref sv = u.encoded_segments();
1879			@endcode
1880
1881			@par Complexity
1882			Constant.
1883
1884			@par Exception Safety
1885			Throws nothing.
1886
1887			@par BNF
1888			@code
1889			path = path-abempty ; begins with "/" or is empty
1890			/ path-absolute ; begins with "/" but not "//"
1891			/ path-noscheme ; begins with a non-colon segment
1892			/ path-rootless ; begins with a segment
1893			/ path-empty ; zero characters
1894
1895			path-abempty = *( "/" segment )
1896			path-absolute = "/" [ segment-nz *( "/" segment ) ]
1897			path-noscheme = segment-nz-nc *( "/" segment )
1898			path-rootless = segment-nz *( "/" segment )
1899			path-empty = 0<pchar>
1900			@endcode
1901
1902			@par Specification
1903			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.3"
1904			>3.3. Path (rfc3986)</a>
1905
1906			@see
1907			@ref encoded_segments,
1908			@ref set_encoded_path,
1909			@ref set_path,
1910			@ref set_path_absolute.
1911			*/
1912			segments_encoded_ref
1913			encoded_segments() noexcept;
1914
1915			/// @copydoc url_view_base::encoded_segments
1916			segments_encoded_view
1917		1	encoded_segments() const noexcept
1918			{
1919		1	return url_view_base::encoded_segments();
1920			}
1921
1922			//--------------------------------------------
1923			//
1924			// Query
1925			//
1926			//--------------------------------------------
1927
1928			/** Set the query
1929
1930			This sets the query to the string, which
1931			can be empty.
1932			An empty query is distinct from having
1933			no query.
1934			Reserved characters in the string are
1935			percent-escaped in the result.
1936
1937			@par Example
1938			@code
1939			assert( url( "http://example.com" ).set_query( "id=42" ).query() == "id=42" );
1940			@endcode
1941
1942			@par Postconditions
1943			@code
1944			this->has_query() == true && this->query() == s
1945			@endcode
1946
1947			@par Exception Safety
1948			Strong guarantee.
1949			Calls to allocate may throw.
1950
1951			@param s The string to set.
1952
1953			@par BNF
1954			@code
1955			query = *( pchar / "/" / "?" )
1956
1957			query-param = key [ "=" value ]
1958			query-params = [ query-param ] *( "&" query-param )
1959			@endcode
1960
1961			@par Specification
1962			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.4"
1963			>3.4. Query (rfc3986)</a>
1964			@li <a href="https://en.wikipedia.org/wiki/Query_string"
1965			>Query string (Wikipedia)</a>
1966
1967			@see
1968			@ref encoded_params,
1969			@ref params,
1970			@ref remove_query,
1971			@ref set_encoded_query.
1972			*/
1973			url_base&
1974			set_query(
1975			core::string_view s);
1976
1977			/** Set the query
1978
1979			This sets the query to the string, which
1980			may contain percent-escapes and can be
1981			empty.
1982			An empty query is distinct from having
1983			no query.
1984			Escapes in the string are preserved,
1985			and reserved characters in the string
1986			are percent-escaped in the result.
1987
1988			@par Example
1989			@code
1990			assert( url( "http://example.com" ).set_encoded_query( "id=42" ).encoded_query() == "id=42" );
1991			@endcode
1992
1993			@par Postconditions
1994			@code
1995			this->has_query() == true && this->query() == decode_view( s );
1996			@endcode
1997
1998			@par Exception Safety
1999			Strong guarantee.
2000			Calls to allocate may throw.
2001			Exceptions thrown on invalid input.
2002
2003			@param s The string to set.
2004
2005			@throws system_error
2006			`s` contains an invalid percent-encoding.
2007
2008			@par BNF
2009			@code
2010			query = *( pchar / "/" / "?" )
2011
2012			query-param = key [ "=" value ]
2013			query-params = [ query-param ] *( "&" query-param )
2014			@endcode
2015
2016			@par Specification
2017			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.4"
2018			>3.4. Query (rfc3986)</a>
2019			@li <a href="https://en.wikipedia.org/wiki/Query_string"
2020			>Query string (Wikipedia)</a>
2021
2022			@see
2023			@ref encoded_params,
2024			@ref params,
2025			@ref remove_query,
2026			@ref set_query.
2027			*/
2028			url_base&
2029			set_encoded_query(
2030			pct_string_view s);
2031
2032			/** Return the query as a container of parameters
2033
2034			This function returns a bidirectional
2035			view of key/value pairs over the query.
2036			The returned view references the same
2037			underlying character buffer; ownership
2038			is not transferred.
2039			Any percent-escapes in strings returned
2040			when iterating the view are decoded first.
2041			The container is modifiable; changes
2042			to the container are reflected in the
2043			underlying URL.
2044
2045			@par Example
2046			@code
2047			params_ref pv = url( "/sql?id=42&name=jane%2Ddoe&page+size=20" ).params();
2048			@endcode
2049
2050			@par Complexity
2051			Constant.
2052
2053			@par Exception Safety
2054			Throws nothing.
2055
2056			@par BNF
2057			@code
2058			query = *( pchar / "/" / "?" )
2059
2060			query-param = key [ "=" value ]
2061			query-params = [ query-param ] *( "&" query-param )
2062			@endcode
2063
2064			@par Specification
2065			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.4"
2066			>3.4. Query (rfc3986)</a>
2067			@li <a href="https://en.wikipedia.org/wiki/Query_string"
2068			>Query string (Wikipedia)</a>
2069
2070			@see
2071			@ref encoded_params,
2072			@ref remove_query,
2073			@ref set_encoded_query,
2074			@ref set_query.
2075			*/
2076			params_ref
2077			params() noexcept;
2078
2079			/// @copydoc url_view_base::params
2080			params_view
2081		1	params() const noexcept
2082			{
2083		1	return url_view_base::params();
2084			}
2085
2086			/** Return the query as a container of parameters
2087
2088			This function returns a bidirectional
2089			view of key/value pairs over the query.
2090			The returned view references the same
2091			underlying character buffer; ownership
2092			is not transferred.
2093			Any percent-escapes in strings returned
2094			when iterating the view are decoded first.
2095			The container is modifiable; changes
2096			to the container are reflected in the
2097			underlying URL.
2098
2099			@par Example
2100			@code
2101			encoding_opts opt;
2102			opt.space_as_plus = true;
2103			params_ref pv = url( "/sql?id=42&name=jane+doe&page+size=20" ).params(opt);
2104			@endcode
2105
2106			@par Complexity
2107			Constant.
2108
2109			@par Exception Safety
2110			Throws nothing.
2111
2112			@param opt The options for decoding. If
2113			this parameter is omitted, the `space_as_plus`
2114			is used.
2115
2116			@par BNF
2117			@code
2118			query = *( pchar / "/" / "?" )
2119
2120			query-param = key [ "=" value ]
2121			query-params = [ query-param ] *( "&" query-param )
2122			@endcode
2123
2124			@par Specification
2125			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.4"
2126			>3.4. Query (rfc3986)</a>
2127			@li <a href="https://en.wikipedia.org/wiki/Query_string"
2128			>Query string (Wikipedia)</a>
2129
2130			@see
2131			@ref encoded_params,
2132			@ref remove_query,
2133			@ref set_encoded_query,
2134			@ref set_query.
2135			*/
2136			params_ref
2137			params(encoding_opts opt) noexcept;
2138
2139			/// @copydoc url_view_base::encoded_params
2140			params_encoded_view
2141		1	encoded_params() const noexcept
2142			{
2143		1	return url_view_base::encoded_params();
2144			}
2145
2146			/** Return the query as a container of parameters
2147
2148			This function returns a bidirectional
2149			view of key/value pairs over the query.
2150			The returned view references the same
2151			underlying character buffer; ownership
2152			is not transferred.
2153			Strings returned when iterating the
2154			range may contain percent escapes.
2155			The container is modifiable; changes
2156			to the container are reflected in the
2157			underlying URL.
2158
2159			@par Example
2160			@code
2161			params_encoded_ref pv = url( "/sql?id=42&name=jane%2Ddoe&page+size=20" ).encoded_params();
2162			@endcode
2163
2164			@par Complexity
2165			Constant.
2166
2167			@par Exception Safety
2168			Throws nothing.
2169
2170			@par BNF
2171			@code
2172			query = *( pchar / "/" / "?" )
2173
2174			query-param = key [ "=" value ]
2175			query-params = [ query-param ] *( "&" query-param )
2176			@endcode
2177
2178			@par Specification
2179			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.4"
2180			>3.4. Query (rfc3986)</a>
2181			@li <a href="https://en.wikipedia.org/wiki/Query_string"
2182			>Query string (Wikipedia)</a>
2183
2184			@see
2185			@ref params,
2186			@ref remove_query,
2187			@ref set_encoded_query,
2188			@ref set_query.
2189			*/
2190			params_encoded_ref
2191			encoded_params() noexcept;
2192
2193			/** Set the query params
2194
2195			This sets the query params to the list
2196			of param_view, which can be empty.
2197
2198			An empty list of params is distinct from
2199			having no params.
2200
2201			Reserved characters in the string are
2202			percent-escaped in the result.
2203
2204			@par Example
2205			@code
2206			assert( url( "http://example.com" ).set_params( {"id", "42"} ).query() == "id=42" );
2207			@endcode
2208
2209			@par Postconditions
2210			@code
2211			this->has_query() == true
2212			@endcode
2213
2214			@par Exception Safety
2215			Strong guarantee.
2216			Calls to allocate may throw.
2217
2218			@par Complexity
2219			Linear.
2220
2221			@param ps The params to set.
2222
2223			@par BNF
2224			@code
2225			query = *( pchar / "/" / "?" )
2226
2227			query-param = key [ "=" value ]
2228			query-params = [ query-param ] *( "&" query-param )
2229			@endcode
2230
2231			@par Specification
2232			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.4
2233			>3.4. Query (rfc3986)</a>
2234			@li <a href="https://en.wikipedia.org/wiki/Query_string"
2235			>Query string (Wikipedia)</a>
2236
2237			@see
2238			@ref encoded_params,
2239			@ref remove_query,
2240			@ref set_encoded_query,
2241			@ref set_query.
2242			*/
2243			url_base&
2244			set_params( std::initializer_list<param_view> ps ) noexcept;
2245
2246			/** Set the query params
2247
2248			This sets the query params to the elements
2249			in the list, which may contain
2250			percent-escapes and can be empty.
2251
2252			An empty list of params is distinct from
2253			having no query.
2254
2255			Escapes in the string are preserved,
2256			and reserved characters in the string
2257			are percent-escaped in the result.
2258
2259			@par Example
2260			@code
2261			assert( url( "http://example.com" ).set_encoded_params( {"id", "42"} ).encoded_query() == "id=42" );
2262			@endcode
2263
2264			@par Postconditions
2265			@code
2266			this->has_query() == true
2267			@endcode
2268
2269			@par Complexity
2270			Linear.
2271
2272			@par Exception Safety
2273			Strong guarantee.
2274			Calls to allocate may throw.
2275			Exceptions thrown on invalid input.
2276
2277			@param ps The params to set.
2278
2279			@throws system_error
2280			some element in `ps` contains an invalid percent-encoding.
2281
2282			@par BNF
2283			@code
2284			query = *( pchar / "/" / "?" )
2285
2286			query-param = key [ "=" value ]
2287			query-params = [ query-param ] *( "&" query-param )
2288			@endcode
2289
2290			@par Specification
2291			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.4"
2292			>3.4. Query (rfc3986)</a>
2293			@li <a href="https://en.wikipedia.org/wiki/Query_string"
2294			>Query string (Wikipedia)</a>
2295
2296			@see
2297			@ref set_params,
2298			@ref params,
2299			@ref remove_query,
2300			@ref set_encoded_query,
2301			@ref set_query.
2302			*/
2303			url_base&
2304			set_encoded_params( std::initializer_list< param_pct_view > ps ) noexcept;
2305
2306			/** Remove the query
2307
2308			If a query is present, it is removed.
2309			An empty query is distinct from having
2310			no query.
2311
2312			@par Example
2313			@code
2314			assert( url( "http://www.example.com?id=42" ).remove_query().buffer() == "http://www.example.com" );
2315			@endcode
2316
2317			@par Postconditions
2318			@code
2319			this->has_query() == false && this->params().empty()
2320			@endcode
2321
2322			@par Exception Safety
2323			Throws nothing.
2324
2325			@par BNF
2326			@code
2327			query = *( pchar / "/" / "?" )
2328
2329			query-param = key [ "=" value ]
2330			query-params = [ query-param ] *( "&" query-param )
2331			@endcode
2332
2333			@par Specification
2334			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.4"
2335			>3.4. Query (rfc3986)</a>
2336			@li <a href="https://en.wikipedia.org/wiki/Query_string"
2337			>Query string (Wikipedia)</a>
2338
2339			@see
2340			@ref encoded_params,
2341			@ref params,
2342			@ref set_encoded_query,
2343			@ref set_query.
2344			*/
2345			url_base&
2346			remove_query() noexcept;
2347
2348			//--------------------------------------------
2349			//
2350			// Fragment
2351			//
2352			//--------------------------------------------
2353
2354			/** Remove the fragment
2355
2356			This function removes the fragment.
2357			An empty fragment is distinct from
2358			having no fragment.
2359
2360			@par Example
2361			@code
2362			assert( url( "?first=john&last=doe#anchor" ).remove_fragment().buffer() == "?first=john&last=doe" );
2363			@endcode
2364
2365			@par Postconditions
2366			@code
2367			this->has_fragment() == false && this->encoded_fragment() == ""
2368			@endcode
2369
2370			@par Complexity
2371			Constant.
2372
2373			@par Exception Safety
2374			Throws nothing.
2375
2376			@par BNF
2377			@code
2378			fragment = *( pchar / "/" / "?" )
2379			@endcode
2380
2381			@par Specification
2382			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.5"
2383			>3.5. Fragment</a>
2384
2385			@see
2386			@ref remove_fragment,
2387			@ref set_encoded_fragment,
2388			@ref set_fragment.
2389			*/
2390			url_base&
2391			remove_fragment() noexcept;
2392
2393			/** Set the fragment.
2394
2395			This function sets the fragment to the
2396			specified string, which may be empty.
2397			An empty fragment is distinct from
2398			having no fragment.
2399			Reserved characters in the string are
2400			percent-escaped in the result.
2401
2402			@par Example
2403			@code
2404			assert( url("?first=john&last=doe" ).set_encoded_fragment( "john doe" ).encoded_fragment() == "john%20doe" );
2405			@endcode
2406
2407			@par Postconditions
2408			@code
2409			this->has_fragment() == true && this->fragment() == s
2410			@endcode
2411
2412			@par Complexity
2413			Linear in `this->size() + s.size()`.
2414
2415			@par Exception Safety
2416			Strong guarantee.
2417			Calls to allocate may throw.
2418
2419			@param s The string to set.
2420
2421			@par BNF
2422			@code
2423			fragment = *( pchar / "/" / "?" )
2424			@endcode
2425
2426			@par Specification
2427			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.5"
2428			>3.5. Fragment</a>
2429
2430			@see
2431			@ref remove_fragment,
2432			@ref set_encoded_fragment.
2433			*/
2434			url_base&
2435			set_fragment(
2436			core::string_view s);
2437
2438			/** Set the fragment.
2439
2440			This function sets the fragment to the
2441			specified string, which may contain
2442			percent-escapes and which may be empty.
2443			An empty fragment is distinct from
2444			having no fragment.
2445			Escapes in the string are preserved,
2446			and reserved characters in the string
2447			are percent-escaped in the result.
2448
2449			@par Example
2450			@code
2451			assert( url("?first=john&last=doe" ).set_encoded_fragment( "john%2Ddoe" ).fragment() == "john-doe" );
2452			@endcode
2453
2454			@par Postconditions
2455			@code
2456			this->has_fragment() == true && this->fragment() == decode_view( s )
2457			@endcode
2458
2459			@par Complexity
2460			Linear in `this->size() + s.size()`.
2461
2462			@par Exception Safety
2463			Strong guarantee.
2464			Calls to allocate may throw.
2465			Exceptions thrown on invalid input.
2466
2467			@throw system_error
2468			`s` contains an invalid percent-encoding.
2469
2470			@param s The string to set.
2471
2472			@par BNF
2473			@code
2474			fragment = *( pchar / "/" / "?" )
2475			@endcode
2476
2477			@par Specification
2478			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-3.5"
2479			>3.5. Fragment</a>
2480
2481			@see
2482			@ref remove_fragment,
2483			@ref set_fragment.
2484			*/
2485			url_base&
2486			set_encoded_fragment(
2487			pct_string_view s);
2488
2489			//--------------------------------------------
2490			//
2491			// Compound Fields
2492			//
2493			//--------------------------------------------
2494
2495			/** Remove the origin component
2496
2497			This function removes the origin, which
2498			consists of the scheme and authority.
2499
2500			@par Example
2501			@code
2502			assert( url( "http://www.example.com/index.htm" ).remove_origin().buffer() == "/index.htm" );
2503			@endcode
2504
2505			@par Postconditions
2506			@code
2507			this->scheme_id() == scheme::none && this->has_authority() == false
2508			@endcode
2509
2510			@par Complexity
2511			Linear in `this->size()`.
2512
2513			@par Exception Safety
2514			Throws nothing.
2515			*/
2516			url_base&
2517			remove_origin();
2518
2519			//--------------------------------------------
2520			//
2521			// Normalization
2522			//
2523			//--------------------------------------------
2524
2525			/** Normalize the URL components
2526
2527			Applies Syntax-based normalization to
2528			all components of the URL.
2529
2530			@par Exception Safety
2531			Strong guarantee.
2532			Calls to allocate may throw.
2533
2534			@par Specification
2535			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-6.2.2"
2536			>6.2.2 Syntax-Based Normalization (rfc3986)</a>
2537
2538			*/
2539			url_base&
2540			normalize();
2541
2542			/** Normalize the URL scheme
2543
2544			Applies Syntax-based normalization to the
2545			URL scheme.
2546
2547			The scheme is normalized to lowercase.
2548
2549			@par Exception Safety
2550			Strong guarantee.
2551			Calls to allocate may throw.
2552
2553			@par Specification
2554			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-6.2.2"
2555			>6.2.2 Syntax-Based Normalization (rfc3986)</a>
2556
2557			*/
2558			url_base&
2559			normalize_scheme();
2560
2561			/** Normalize the URL authority
2562
2563			Applies Syntax-based normalization to the
2564			URL authority.
2565
2566			Percent-encoding triplets are normalized
2567			to uppercase letters. Percent-encoded
2568			octets that correspond to unreserved
2569			characters are decoded.
2570
2571			@par Exception Safety
2572			Strong guarantee.
2573			Calls to allocate may throw.
2574
2575			@par Specification
2576			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-6.2.2"
2577			>6.2.2 Syntax-Based Normalization (rfc3986)</a>
2578
2579			*/
2580			url_base&
2581			normalize_authority();
2582
2583			/** Normalize the URL path
2584
2585			Applies Syntax-based normalization to the
2586			URL path.
2587
2588			Percent-encoding triplets are normalized
2589			to uppercase letters. Percent-encoded
2590			octets that correspond to unreserved
2591			characters are decoded. Redundant
2592			path-segments are removed.
2593
2594			@par Exception Safety
2595			Strong guarantee.
2596			Calls to allocate may throw.
2597
2598			@par Specification
2599			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-6.2.2"
2600			>6.2.2 Syntax-Based Normalization (rfc3986)</a>
2601
2602			*/
2603			url_base&
2604			normalize_path();
2605
2606			/** Normalize the URL query
2607
2608			Applies Syntax-based normalization to the
2609			URL query.
2610
2611			Percent-encoding triplets are normalized
2612			to uppercase letters. Percent-encoded
2613			octets that correspond to unreserved
2614			characters are decoded.
2615
2616			@par Exception Safety
2617			Strong guarantee.
2618			Calls to allocate may throw.
2619
2620			@par Specification
2621			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-6.2.2"
2622			>6.2.2 Syntax-Based Normalization (rfc3986)</a>
2623
2624			*/
2625			url_base&
2626			normalize_query();
2627
2628			/** Normalize the URL fragment
2629
2630			Applies Syntax-based normalization to the
2631			URL fragment.
2632
2633			Percent-encoding triplets are normalized
2634			to uppercase letters. Percent-encoded
2635			octets that correspond to unreserved
2636			characters are decoded.
2637
2638			@par Exception Safety
2639			Strong guarantee.
2640			Calls to allocate may throw.
2641
2642			@par Specification
2643			@li <a href="https://datatracker.ietf.org/doc/html/rfc3986#section-6.2.2"
2644			>6.2.2 Syntax-Based Normalization (rfc3986)</a>
2645
2646			*/
2647			url_base&
2648			normalize_fragment();
2649
2650			//
2651			// (end of fluent API)
2652			//
2653			//--------------------------------------------
2654
2655			//--------------------------------------------
2656			//
2657			// Resolution
2658			//
2659			//--------------------------------------------
2660
2661			/** Resolve a URL reference against this base URL
2662
2663			This function attempts to resolve a URL
2664			reference `ref` against this base URL
2665			in a manner similar to that of a web browser
2666			resolving an anchor tag.
2667
2668			This URL must satisfy the <em>URI</em>
2669			grammar. In other words, it must contain
2670			a scheme.
2671
2672			Relative references are only usable when
2673			in the context of a base absolute URI.
2674			This process of resolving a relative
2675			<em>reference</em> within the context of
2676			a <em>base</em> URI is defined in detail
2677			in rfc3986 (see below).
2678
2679			The resolution process works as if the
2680			relative reference is appended to the base
2681			URI and the result is normalized.
2682
2683			Given the input base URL, this function
2684			resolves the relative reference
2685			as if performing the following steps:
2686
2687			@li Ensure the base URI has at least a scheme
2688			@li Normalizing the reference path
2689			@li Merge base and reference paths
2690			@li Normalize the merged path
2691
2692			This function places the result of the
2693			resolution into this URL in place.
2694
2695			If an error occurs, the contents of
2696			this URL are unspecified and a @ref result
2697			with an `system::error_code` is returned.
2698
2699			@par Example
2700			@code
2701			url base1( "/one/two/three" );
2702			base1.resolve("four");
2703			assert( base1.buffer() == "/one/two/four" );
2704
2705			url base2( "http://example.com/" )
2706			base2.resolve("/one");
2707			assert( base2.buffer() == "http://example.com/one" );
2708
2709			url base3( "http://example.com/one" );
2710			base3.resolve("/two");
2711			assert( base3.buffer() == "http://example.com/two" );
2712
2713			url base4( "http://a/b/c/d;p?q" );
2714			base4.resolve("g#s");
2715			assert( base4.buffer() == "http://a/b/c/g#s" );
2716			@endcode
2717
2718			@par BNF
2719			@code
2720			absolute-URI = scheme ":" hier-part [ "?" query ]
2721			@endcode
2722
2723			@par Exception Safety
2724			Basic guarantee.
2725			Calls to allocate may throw.
2726
2727			@return An empty @ref result upon success,
2728			otherwise an error code if `!base.has_scheme()`.
2729
2730			@param ref The URL reference to resolve.
2731
2732			@par Specification
2733			<a href="https://datatracker.ietf.org/doc/html/rfc3986#section-5"
2734			>5. Reference Resolution (rfc3986)</a>
2735
2736			@see
2737			@ref url,
2738			@ref url_view.
2739			*/
2740			system::result<void>
2741			resolve(
2742			url_view_base const& ref);
2743
2744			friend
2745			system::result<void>
2746			resolve(
2747			url_view_base const& base,
2748			url_view_base const& ref,
2749			url_base& dest);
2750
2751			private:
2752			//--------------------------------------------
2753			//
2754			// implementation
2755			//
2756			//--------------------------------------------
2757
2758			void check_invariants() const noexcept;
2759
2760			char* resize_impl(int, std::size_t, op_t&);
2761			char* resize_impl(int, int, std::size_t, op_t&);
2762			char* shrink_impl(int, std::size_t, op_t&);
2763			char* shrink_impl(int, int, std::size_t, op_t&);
2764
2765			void set_scheme_impl(core::string_view, urls::scheme);
2766			char* set_user_impl(std::size_t n, op_t& op);
2767			char* set_password_impl(std::size_t n, op_t& op);
2768			char* set_userinfo_impl(std::size_t n, op_t& op);
2769			char* set_host_impl(std::size_t n, op_t& op);
2770			char* set_port_impl(std::size_t n, op_t& op);
2771			char* set_path_impl(std::size_t n, op_t& op);
2772
2773			core::string_view
2774			first_segment() const noexcept;
2775
2776			detail::segments_iter_impl
2777			edit_segments(
2778			detail::segments_iter_impl const&,
2779			detail::segments_iter_impl const&,
2780			detail::any_segments_iter&& it0,
2781			int absolute = -1);
2782
2783			auto
2784			edit_params(
2785			detail::params_iter_impl const&,
2786			detail::params_iter_impl const&,
2787			detail::any_params_iter&&) ->
2788			detail::params_iter_impl;
2789
2790			system::result<void>
2791			resolve_impl(
2792			url_view_base const& base,
2793			url_view_base const& ref);
2794
2795			template<class CharSet>
2796			void normalize_octets_impl(int,
2797			CharSet const& allowed, op_t&) noexcept;
2798			void decoded_to_lower_impl(int id) noexcept;
2799			void to_lower_impl(int id) noexcept;
2800			};
2801
2802			//------------------------------------------------
2803
2804			/** Resolve a URL reference against a base URL
2805
2806			This function attempts to resolve a URL
2807			reference `ref` against the base URL `base`
2808			in a manner similar to that of a web browser
2809			resolving an anchor tag.
2810
2811			The base URL must satisfy the <em>URI</em>
2812			grammar. In other words, it must contain
2813			a scheme.
2814
2815			Relative references are only usable when
2816			in the context of a base absolute URI.
2817			This process of resolving a relative
2818			<em>reference</em> within the context of
2819			a <em>base</em> URI is defined in detail
2820			in rfc3986 (see below).
2821
2822			The resolution process works as if the
2823			relative reference is appended to the base
2824			URI and the result is normalized.
2825
2826			Given the input base URL, this function
2827			resolves the relative reference
2828			as if performing the following steps:
2829
2830			@li Ensure the base URI has at least a scheme
2831			@li Normalizing the reference path
2832			@li Merge base and reference paths
2833			@li Normalize the merged path
2834
2835			This function places the result of the
2836			resolution into `dest`, which can be
2837			any of the url containers that inherit
2838			from @ref url_base.
2839
2840			If an error occurs, the contents of
2841			`dest` is unspecified and `ec` is set.
2842
2843			@par Example
2844			@code
2845			url dest;
2846			system::error_code ec;
2847
2848			resolve("/one/two/three", "four", dest, ec);
2849			assert( dest.str() == "/one/two/four" );
2850
2851			resolve("http://example.com/", "/one", dest, ec);
2852			assert( dest.str() == "http://example.com/one" );
2853
2854			resolve("http://example.com/one", "/two", dest, ec);
2855			assert( dest.str() == "http://example.com/two" );
2856
2857			resolve("http://a/b/c/d;p?q", "g#s", dest, ec);
2858			assert( dest.str() == "http://a/b/c/g#s" );
2859			@endcode
2860
2861			@par BNF
2862			@code
2863			absolute-URI = scheme ":" hier-part [ "?" query ]
2864			@endcode
2865
2866			@par Exception Safety
2867			Basic guarantee.
2868			Calls to allocate may throw.
2869
2870			@return An empty @ref result upon success,
2871			otherwise an error code if `!base.has_scheme()`.
2872
2873			@param base The base URL to resolve against.
2874
2875			@param ref The URL reference to resolve.
2876
2877			@param dest The container where the result
2878			is written, upon success.
2879
2880			@par Specification
2881			<a href="https://datatracker.ietf.org/doc/html/rfc3986#section-5"
2882			>5. Reference Resolution (rfc3986)</a>
2883
2884			@see
2885			@ref url,
2886			@ref url_view.
2887			*/
2888			inline
2889			system::result<void>
2890		396	resolve(
2891			url_view_base const& base,
2892			url_view_base const& ref,
2893			url_base& dest)
2894			{
2895	2/2 ✓ Branch 0 taken 395 times. ✓ Branch 1 taken 1 times.	396	if (&dest != &base)
2896		395	dest.copy(base);
2897		396	return dest.resolve(ref);
2898			}
2899
2900			} // urls
2901			} // boost
2902
2903			// These are here because of circular references
2904			#include <boost/url/impl/params_ref.hpp>
2905			#include <boost/url/impl/params_encoded_ref.hpp>
2906			#include <boost/url/impl/segments_ref.hpp>
2907			#include <boost/url/impl/segments_encoded_ref.hpp>
2908
2909			#endif
2910