NAME
Eval::Util - Utilities related to eval()
VERSION
This document describes version 0.002 of Eval::Util (from Perl
distribution Eval-Util), released on 2018-03-12.
SYNOPSIS
use Eval::Util qw(
inside_eval
inside_block_eval
inside_string_eval
eval_level
);
# will not print 'foo', but print 'bar' and 'baz'
say "foo" if inside_eval();
eval { say "bar" if inside_eval() };
eval q(say "baz" if inside_eval());
# will not print 'foo' or 'baz' but print 'bar'
say "foo" if inside_block_eval();
eval { say "bar" if inside_block_eval() };
eval q(say "baz" if inside_block_eval());
# will not print 'foo' or 'bar' but print 'baz'
say "foo" if inside_string_eval();
eval { say "bar" if inside_string_eval() };
eval q(say "baz" if inside_string_eval());
say eval_level(); # 0
eval { say eval_level() }; # 1
eval { eval { say eval_level() } }; # 2
DESCRIPTION
FUNCTIONS
None exported by default, but they are exportable.
inside_eval
Usage: inside_eval() => bool
Will check if running code is inside eval() (either string eval or block
eval). This is done via examining the stack trace and checking for frame
with subroutine named "(eval)".
A faster and simpler alternative is to check if the Perl special
variable $^S is true. Consult perlvar for more details about this
variable.
inside_block_eval
Usage: inside_block_eval() => bool
Will check if running code is inside block eval() ("eval { ... }"). Will
return false if code is only inside string eval. This is done via
examining the stack trace and checking for frame with subroutine named
"(eval)" that has undefined eval text.
inside_string_eval
Usage: inside_string_eval() => bool
Will check if running code is inside string eval() ("eval " ... "").
Will return false if code is only inside block eval. This is done via
examining the stack trace and checking for frame with subroutine named
"(eval)" that has defined eval text.
eval_level
Usage: eval_level() => int
Return 0 if running code is not inside any eval, 1 if inside one eval, 2
if inside two evals, and so on.
HOMEPAGE
Please visit the project's homepage at
<https://metacpan.org/release/Eval-Util>.
SOURCE
Source repository is at <https://github.com/perlancar/perl-Eval-Util>.
BUGS
Please report any bugs or feature requests on the bugtracker website
<https://rt.cpan.org/Public/Dist/Display.html?Name=Eval-Util>
When submitting a bug or request, please include a test-file or a patch
to an existing test-file that illustrates the bug or desired feature.
SEE ALSO
"caller" in perlfunc
$^S in perlvar
AUTHOR
perlancar <perlancar@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2018 by perlancar@cpan.org.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.