| 1 | package integer; |
| 2 | |
| 3 | =head1 NAME |
| 4 | |
| 5 | integer - Perl pragma to compute arithmetic in integer instead of double |
| 6 | |
| 7 | =head1 SYNOPSIS |
| 8 | |
| 9 | use integer; |
| 10 | $x = 10/3; |
| 11 | # $x is now 3, not 3.33333333333333333 |
| 12 | |
| 13 | =head1 DESCRIPTION |
| 14 | |
| 15 | This tells the compiler to use integer operations |
| 16 | from here to the end of the enclosing BLOCK. On many machines, |
| 17 | this doesn't matter a great deal for most computations, but on those |
| 18 | without floating point hardware, it can make a big difference. |
| 19 | |
| 20 | Note that this affects the operations, not the numbers. If you run this |
| 21 | code |
| 22 | |
| 23 | use integer; |
| 24 | $x = 1.5; |
| 25 | $y = $x + 1; |
| 26 | $z = -1.5; |
| 27 | |
| 28 | you'll be left with C<$x == 1.5>, C<$y == 2> and C<$z == -1>. The $z |
| 29 | case happens because unary C<-> counts as an operation. |
| 30 | |
| 31 | See L<perlmod/Pragmatic Modules>. |
| 32 | |
| 33 | =cut |
| 34 | |
| 35 | sub import { |
| 36 | $^H |= 1; |
| 37 | } |
| 38 | |
| 39 | sub unimport { |
| 40 | $^H &= ~1; |
| 41 | } |
| 42 | |
| 43 | 1; |