phpman > perldoc > Eval::TypeTiny(3pm)

NAME
    Eval::TypeTiny - utility to evaluate a string of Perl code in a clean environment

STATUS
    This module is covered by the Type-Tiny stability policy.

DESCRIPTION
    This module is used by Type::Tiny to compile coderefs from strings of Perl code, and hashrefs of
    variables to close over.

  Functions
    This module exports one function, which works much like the similarly named function from
    Eval::Closure:

    "eval_closure(source => $source, environment => \%env, %opt)"

  Constants
    The following constants may be exported, but are not by default.

    "HAS_LEXICAL_SUBS"
        Boolean indicating whether Eval::TypeTiny has support for lexical subs. (This feature
        requires Perl 5.18.)

    "ALIAS_IMPLEMENTATION"
        Returns a string indicating what implementation of "alias => 1" is being used.
        Eval::TypeTiny will automatically choose the best implementation. This constant can be
        matched against the "IMPLEMENTAION_*" constants.

    "IMPLEMENTATION_NATIVE"
        If "ALIAS_IMPLEMENTATION eq IMPLEMENTATION_NATIVE" then Eval::TypeTiny is currently using
        Perl 5.22's native alias feature. This requires Perl 5.22.

    "IMPLEMENTATION_DEVEL_LEXALIAS"
        If "ALIAS_IMPLEMENTATION eq IMPLEMENTATION_DEVEL_LEXALIAS" then Eval::TypeTiny is currently
        using Devel::LexAlias to provide aliases.

    "IMPLEMENTATION_PADWALKER"
        If "ALIAS_IMPLEMENTATION eq IMPLEMENTATION_PADWALKER" then Eval::TypeTiny is currently using
        PadWalker to provide aliases.

    "IMPLEMENTATION_TIE"
        If "ALIAS_IMPLEMENTATION eq IMPLEMENTATION_TIE" then Eval::TypeTiny is using the fallback
        implementation of aliases using "tie". This is the slowest implementation, and may cause
        problems in certain edge cases, like trying to alias already-tied variables, but it's the
        only way to implement "alias => 1" without a recent version of Perl or one of the two
        optional modules mentioned above.

EVALUATION ENVIRONMENT
    The evaluation is performed in the presence of strict, but the absence of warnings. (This is
    different to Eval::Closure which enables warnings for compiled closures.)

    The feature pragma is not active in the evaluation environment, so the following will not work:

       use feature qw(say);
       use Eval::TypeTiny qw(eval_closure);

       my $say_all = eval_closure(
          source => 'sub { say for @_ }',
       );
       $say_all->("Hello", "World");

    The feature pragma does not "carry over" into the stringy eval. It is of course possible to
    import pragmas into the evaluated string as part of the string itself:

       use Eval::TypeTiny qw(eval_closure);

       my $say_all = eval_closure(
          source => 'sub { use feature qw(say); say for @_ }',
       );
       $say_all->("Hello", "World");

BUGS
    Please report any bugs to <https://github.com/tobyink/p5-type-tiny/issues>.

SEE ALSO
    Eval::Closure, Error::TypeTiny::Compilation.

AUTHOR
    Toby Inkster <tobyink AT cpan.org>.

COPYRIGHT AND LICENCE
    This software is copyright (c) 2013-2014, 2017-2021 by Toby Inkster.

    This is free software; you can redistribute it and/or modify it under the same terms as the Perl
    5 programming language system itself.

DISCLAIMER OF WARRANTIES
    THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
    WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
    PURPOSE.