Syntax::Keyword::Assert - assert keyword for Perl with zero runtime cost
use Syntax::Keyword::Assert;
my $obj = bless {}, "Foo";
assert($obj isa "Bar");
# => Assertion failed (Foo=HASH(0x11e022818) isa "Bar")Syntax::Keyword::Assert provides a syntax extension for Perl that introduces a assert keyword.
By default assertions are enabled, but can be disabled by setting $ENV{PERL_ASSERT_ENABLED} to false before this module is loaded:
BEGIN { $ENV{PERL_ASSERT_ENABLED} = 0 } # Disable assertions
When assertions are disabled, the assert are completely ignored at compile phase, resulting in zero runtime cost. This makes Syntax::Keyword::Assert ideal for use in production environments, as it does not introduce any performance penalties when assertions are not needed.
assert(EXPR)
If EXPR is truthy in scalar context, then happens nothing. Otherwise, it dies with a user-friendly error message.
Here are some examples:
assert("apple" eq "banana"); # => Assertion failed ("apple" eq "banana")
assert(123 != 123); # => Assertion failed (123 != 123)
assert(1 > 10); # => Assertion failed (1 > 10)-
This module also uses keyword plugin, but it depends on Keyword::Simple. And this module's error message does not include the failed expression.
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This module provides a similar functionality, but it dose not use a keyword plugin.
Copyright (C) kobaken.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
kobaken [email protected]