diff options
Diffstat (limited to 'pod/perlnumber.pod')
| -rw-r--r-- | pod/perlnumber.pod | 60 |
1 files changed, 43 insertions, 17 deletions
diff --git a/pod/perlnumber.pod b/pod/perlnumber.pod index 44d921cfe6..aaf729eb58 100644 --- a/pod/perlnumber.pod +++ b/pod/perlnumber.pod @@ -4,15 +4,15 @@ perlnumber - semantics of numbers and numeric operations in Perl =head1 SYNOPSIS - $n = 1234; # decimal integer - $n = 0b1110011; # binary integer - $n = 01234; # octal integer - $n = 0x1234; # hexadecimal integer - $n = 12.34e-56; # exponential notation - $n = "-12.34e56"; # number specified as a string - $n = "1234"; # number specified as a string - $n = v49.50.51.52; # number specified as a string, which in - # turn is specified in terms of numbers :-) + $n = 1234; # decimal integer + $n = 0b1110011; # binary integer + $n = 01234; # octal integer + $n = 0x1234; # hexadecimal integer + $n = 12.34e-56; # exponential notation + $n = "-12.34e56"; # number specified as a string + $n = "1234"; # number specified as a string + $n = v49.50.51.52; # number specified as a string, which in + # turn is specified in terms of numbers :-) =head1 DESCRIPTION @@ -143,19 +143,43 @@ C<sprintf "%u", ~0>. =over 4 -=item Arithmetic operators except, C<no integer> +=item Arithmetic operators -force the argument into the floating point format. +The binary operators C<+> C<-> C<*> C</> C<%> C<==> C<!=> C<E<gt>> C<E<lt>> +C<E<gt>=> C<E<lt>=> and the unary operators C<-> C<abs> and C<--> will +attempt to convert arguments to integers. If both conversions are possible +without loss of precision, and the operation can be performed without +loss of precision then the integer result is used. Otherwise arguments are +converted to floating point format and the floating point result is used. +The caching of conversions (as described above) means that the integer +conversion does not throw away fractional parts on floating point numbers. -=item Arithmetic operators except, C<use integer> +=item ++ -=item Bitwise operators, C<no integer> +C<++> behaves as the other operators above, except that if it is a string +matching the format C</^[a-zA-Z]*[0-9]*\z/> the string increment described +in L<perlop> is used. -force the argument into the integer format if it is not a string. +=item Arithmetic operators during C<use integer> -=item Bitwise operators, C<use integer> +In scopes where C<use integer;> is in force, nearly all the operators listed +above will force their argument(s) into integer format, and return an integer +result. The exceptions, C<abs>, C<++> and C<-->, do not change their +behavior with C<use integer;> -force the argument into the integer format +=item Other mathematical operators + +Operators such as C<**>, C<sin> and C<exp> force arguments to floating point +format. + +=item Bitwise operators + +Arguments are forced into the integer format if not strings. + +=item Bitwise operators during C<use integer> + +forces arguments to integer format. Also shift operations internally use +signed integers rather than the default unsigned. =item Operators which expect an integer @@ -180,6 +204,8 @@ Ilya Zakharevich C<ilya@math.ohio-state.edu> Editorial adjustments by Gurusamy Sarathy <gsar@ActiveState.com> +Updates for 5.8.0 by Nicholas Clark <nick@ccl4.org> + =head1 SEE ALSO -L<overload> +L<overload>, L<perlop> |