NAME

Syntax::Operator::Divides - an infix operator for division test

SYNOPSIS

On Perl v5.38 or later:

use Syntax::Operator::Divides;

say "Multiple of 10" if $x %% 10;

Or via Syntax::Keyword::Match on Perl v5.14 or later:

use v5.14;
use Syntax::Keyword::Match;
use Syntax::Operator::Divides;

foreach ( 1 .. 100 ) {
   match( $_ : %% ) {
      case(15) { say "FizzBuzz" }
      case(3)  { say "Fizz" }
      case(5)  { say "Buzz" }
      default  { say $_ }
   }
}

DESCRIPTION

This module provides an infix operator that implements an integer divides test which returns true if the lefthand operand is a whole multiple of the righthand.

Support for custom infix operators was added in the Perl 5.37.x development cycle and is available from development release v5.37.7 onwards, and therefore in Perl v5.38 onwards. The documentation of XS::Parse::Infix describes the situation in more detail.

While Perl versions before this do not support custom infix operators, they can still be used via XS::Parse::Infix and hence XS::Parse::Keyword. Custom keywords which attempt to parse operator syntax may be able to use these. One such module is Syntax::Keyword::Match; see the SYNOPSIS example given above.

OPERATORS

%%

my $divides = $numerator %% $denominator;

Yields true if the numerator operand is a whole integer multiple of the denominator. This is implemented by using the % modulus operator and testing if the remainder is zero.

FUNCTIONS

As a convenience, the following functions may be imported which implement the same behaviour as the infix operators, though are accessed via regular function call syntax.

These wrapper functions are implemented using XS::Parse::Infix, and thus have an optimising call-checker attached to them. In most cases, code which calls them should not in fact have the full runtime overhead of a function call because the underlying test operator will get inlined into the calling code at compiletime. In effect, code calling these functions should run with the same performance as code using the infix operators directly.

is_divisor

my $divides = is_divisor( $numerator, $denominator );

A function version of the "%%" operator.

AUTHOR

Paul Evans <leonerd@leonerd.org.uk>