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Defined in header
constexprstd::chrono::secondsoperator""s(unsignedlonglongsecs); (1) (since C++14)constexprstd::chrono::duration</*unspecified*/>operator""s(longdoublesecs); (2) (since C++14)Forms a
literal representing seconds.
1) Integer literal, returns exactly std::chrono::seconds(secs).
2) Floating-point literal, returns a floating-point duration equivalent to
.
Parameters
secs - the number of seconds Return value
The
literal.
Possible implementation
constexprstd::chrono::secondsoperator""s(unsignedlonglongs){returnstd::chrono::seconds(s);}constexprstd::chrono::duration<longdouble>operator""s(longdoubles){returnstd::chrono::duration<longdouble>(s);}Notes
This operator is declared in the namespace std::literals::chrono_literals, where both literals and chrono_literals are
. Access to this operator can be gained with:
usingnamespacestd::literals,
usingnamespacestd::chrono_literals, or
usingnamespacestd::literals::chrono_literals.
In addition, within the namespace std::chrono, the directive usingnamespaceliterals::chrono_literals; is provided by the
, so that if a programmer uses usingnamespacestd::chrono; to gain access to the classes in the
, the corresponding literal operators become visible as well.
also defines operator""s, to represent literal objects of type std::string, but it is a string literal: 10s is ten seconds, but "10"s is a two-character string.
Example
Run this code
#include<chrono>#include<iostream>intmain(){usingnamespacestd::chrono_literals;std::chrono::secondshalfmin=30s;std::cout<<"Half a minute is "<<halfmin.count()<<" seconds"" ("<<halfmin<<").\n""A minute and a second is "<<(1min+1s).count()<<" seconds.\n";std::chrono::durationmoment=0.1s;std::cout<<"A moment is "<<moment.count()<<" seconds"" ("<<moment<<").\n""And thrice as much is "<<(moment+0.2s).count()<<" seconds.\n";}Output:
Half a minute is 30 seconds (30s). A minute and a second is 61 seconds. A moment is 0.1 seconds (0.1s). And thrice as much is 0.3 seconds. See also
constructs new duration
(public member function of std::chrono::duration<Rep,Period>)