cpp/string/basic string/pop back - Revision history

Xmcgcg: Applied P3471R4 (Standard Library Hardening).

2025-03-27T09:03:08Z

Applied P3471R4 (Standard Library Hardening).

← Older revision		Revision as of 09:03, 27 March 2025
Line 7:		Line 7:
	Removes the last character from the string.		Removes the last character from the string.

	Equivalent to {{c\|erase(end() - 1)}}~~. The behavior is undefined if the string is empty~~.		Equivalent to {{c\|erase(end() - 1)}}.

	=~~==Parameters===~~		{{cpp/hardened ub if\|since=c++26\|{{lc\|empty()}} is {{c\|true}}}}
	~~(none)~~

	~~===Return value===~~
	(~~none~~)

	===Complexity===		===Complexity===

Space Mission: {{ddcla}}

2024-10-18T22:10:45Z

← Older revision		Revision as of 22:10, 18 October 2024
Line 1:		Line 1:
	{{cpp/string/basic_string/title\|pop_back}}		{{cpp/string/basic_string/title\|pop_back}}
	{{cpp/string/basic_string/navbar}}		{{cpp/string/basic_string/navbar}}
	{{~~ddcl~~\|~~notes~~=~~{{mark constexpr since~~ c++20}}\|1=		{{ddcla\|constexpr=c++20\|
	void pop_back();		void pop_back();
	}}		}}
Line 35:		Line 35:
	{		{
	std::string str("Short string!");		std::string str("Short string!");
	std::cout << "~~before=~~" << std::quoted(str) << '\n';		std::cout << "Before: " << std::quoted(str) << '\n';
	assert(str.size() == 13);		assert(str.size() == 13);

	str.pop_back();		str.pop_back();
	std::cout << " ~~after=~~" << std::quoted(str) << '\n';		std::cout << "After: " << std::quoted(str) << '\n';
	assert(str.size() == 12);		assert(str.size() == 12);

Line 46:		Line 46:
	}		}
	\|output=		\|output=
	~~before=~~"Short string!"		Before: "Short string!"
	~~after=~~"Short string"		After: "Short string"
	}}		}}

Space Mission: /* Synopsis */ =

2024-04-21T19:19:23Z

Synopsis: =

← Older revision		Revision as of 19:19, 21 April 2024
Line 1:		Line 1:
	{{cpp/string/basic_string/title\|pop_back}}		{{cpp/string/basic_string/title\|pop_back}}
	{{cpp/string/basic_string/navbar}}		{{cpp/string/basic_string/navbar}}
	{{~~dcl begin~~}}		{{ddcl\|notes={{mark constexpr since c++20}}\|1=
	~~{{dcl rev multi~~
	\|~~dcl1~~=
	void pop_back();		void pop_back();
	~~\|since2=c++20\|dcl2=~~
	~~constexpr void pop_back();~~
	}}		}}
	~~{{dcl end}}~~

	Removes the last character from the string.		Removes the last character from the string.

Andreas Krug: headers sorted

2023-06-02T17:39:25Z

headers sorted

← Older revision		Revision as of 17:39, 2 June 2023
Line 33:		Line 33:
	\|code=		\|code=
	#include <cassert>		#include <cassert>
	~~#include <string>~~
	#include <iomanip>		#include <iomanip>
	#include <iostream>		#include <iostream>
			#include <string>

	int main()		int main()

Xmcgcg: Added a note about the libstdc++ conformance of LWG 534.

2023-05-31T09:22:38Z

Added a note about the libstdc++ conformance of LWG 534.

← Older revision		Revision as of 09:22, 31 May 2023
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	===Exceptions===		===Exceptions===
	Throws nothing.		Throws nothing.

			===Notes===
			In libstdc++, {{tt\|pop_back()}} is [https://gcc.gnu.org/onlinedocs/libstdc++/manual/strings.html#strings.string.shrink not available] in C++98 mode.

	===Example===		===Example===

Xmcgcg: Added LWG issue #534 DR (part 3/3).

2023-02-23T02:39:29Z

Added LWG issue #534 DR (part 3/3).

← Older revision		Revision as of 02:39, 23 February 2023
Line 1:		Line 1:
	{{cpp/string/basic_string/title \| pop_back}}		{{cpp/string/basic_string/title\|pop_back}}
	{{cpp/string/basic_string/navbar}}		{{cpp/string/basic_string/navbar}}
	{{dcl begin}}		{{dcl begin}}
	{{dcl rev multi		{{dcl rev multi
	~~\| since1=c++11~~ \| dcl1=		\|dcl1=
	void pop_back();		void pop_back();
	\| since2=c++20 \| dcl2=		\|since2=c++20\|dcl2=
	constexpr void pop_back();		constexpr void pop_back();
	}}		}}
Line 12:		Line 12:
	Removes the last character from the string.		Removes the last character from the string.

	Equivalent to {{c\|erase(end()-1)}}. The behavior is undefined if the string is empty.		Equivalent to {{c\|erase(end() - 1)}}. The behavior is undefined if the string is empty.

	===Parameters===		===Parameters===
Line 28:		Line 28:
	===Example===		===Example===
	{{example		{{example
	\| code=		\|code=
	#include <cassert>		#include <cassert>
	#include <string>		#include <string>
Line 37:		Line 37:
	{		{
	std::string str("Short string!");		std::string str("Short string!");
	std::cout << "before=" << quoted(str) << '\n';		std::cout << "before=" << std::quoted(str) << '\n';
	assert(str.size() == 13);		assert(str.size() == 13);

	str.pop_back();		str.pop_back();
	std::cout << " after=" << quoted(str) << '\n';		std::cout << " after=" << std::quoted(str) << '\n';
	assert(str.size() == 12);		assert(str.size() == 12);

	str.clear();		str.clear();
	// str.pop_back(); // ~~UB!~~		// str.pop_back(); // undefined behavior
	}		}
	\| output=		\|output=
	before="Short string!"		before="Short string!"
	after="Short string"		after="Short string"
	}}		}}

			===Defect reports===
			{{dr list begin}}
			{{dr list item\|wg=lwg\|dr=534\|std=C++98\|before={{lc\|std::basic_string}} did not have the member function {{tt\|pop_back()}}\|after=added}}
			{{dr list end}}

	===See also===		===See also===

	{{dsc begin}}		{{dsc begin}}
	{{dsc inc \| cpp/string/basic_string/dsc push_back}}		{{dsc inc\|cpp/string/basic_string/dsc push_back}}
	{{dsc inc \| cpp/string/basic_string/dsc erase}}		{{dsc inc\|cpp/string/basic_string/dsc erase}}
	{{dsc end}}		{{dsc end}}

	{{langlinks\|de\|es\|fr\|it\|ja\|pt\|ru\|zh}}		{{langlinks\|de\|es\|fr\|it\|ja\|pt\|ru\|zh}}

Space Mission: /* Example */ minor updates

2022-01-19T23:31:14Z

Example: minor updates

← Older revision		Revision as of 23:31, 19 January 2022
Line 31:		Line 31:
	#include <cassert>		#include <cassert>
	#include <string>		#include <string>
			#include <iomanip>
	#include <iostream>		#include <iostream>

	int main()		int main()
	{		{
	std::string str("Short string");		std::string str("Short string!");
	std::cout << "before='" << str << "'\n";		std::cout << "before=" << quoted(str) << '\n';
			assert(str.size() == 13);

			str.pop_back();
			std::cout << " after=" << quoted(str) << '\n';
	assert(str.size() == 12);		assert(str.size() == 12);

	str.~~pop_back~~();		str.clear();
	~~std::cout << " after='" << str << "'\n";~~		// str.pop_back(); // UB!
	~~assert(~~str.~~size~~(~~) == 11~~);
	}		}
	\| output=		\| output=
	before='Short string'		before="Short string!"
	after='Short ~~strin'~~		after="Short string"
	}}		}}

Elbarto: Add simple example

2022-01-18T22:34:29Z

Add simple example

@@ Line 25: / Line 25: @@
 ===Exceptions===
 Throws nothing.
 ===See also===

Fruderica: P0980R1

2020-02-18T08:04:32Z

P0980R1

← Older revision		Revision as of 08:04, 18 February 2020
Line 1:		Line 1:
	{{cpp/string/basic_string/title \| pop_back}}		{{cpp/string/basic_string/title \| pop_back}}
	{{cpp/string/basic_string/navbar}}		{{cpp/string/basic_string/navbar}}
	{{~~ddcl~~ \| ~~since~~=c++11 \|		{{dcl begin}}
			{{dcl rev multi
			\| since1=c++11 \| dcl1=
	void pop_back();		void pop_back();
			\| since2=c++20 \| dcl2=
			constexpr void pop_back();
	}}		}}
			{{dcl end}}

	Removes the last character from the string.		Removes the last character from the string.
Line 28:		Line 33:
	{{dsc end}}		{{dsc end}}

	[[de~~:cpp/string/basic string/pop back]]~~		{{langlinks\|de\|es\|fr\|it\|ja\|pt\|ru\|zh}}
	[[es~~:cpp/string/basic string/pop back]]~~
	[[fr~~:cpp/string/basic string/pop back]]~~
	[[it~~:cpp/string/basic string/pop back]]~~
	[[ja~~:cpp/string/basic string/pop back]]~~
	[[pt~~:cpp/string/basic string/pop back]]~~
	[[ru~~:cpp/string/basic string/pop back]]~~
	[[zh~~:cpp/string/basic string/pop back]]~~

T. Canens: +

2018-11-20T23:02:26Z

← Older revision		Revision as of 23:02, 20 November 2018
Line 7:		Line 7:
	Removes the last character from the string.		Removes the last character from the string.

	Equivalent to {{c\|erase(~~size~~()-1, 1)}}~~, except the~~ behavior is undefined if the string is empty.		Equivalent to {{c\|erase(end()-1)}}. The behavior is undefined if the string is empty.

	===Parameters===		===Parameters===
Line 19:		Line 19:

	===Exceptions===		===Exceptions===
	~~Does not throw~~		Throws nothing.

	===See also===		===See also===