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NAME
    Eval::WithLexicals - pure perl eval with persistent lexical variables

SYNOPSIS
      # file: bin/tinyrepl

      #!/usr/bin/env perl

      use strictures 1;
      use Eval::WithLexicals;
      use Term::ReadLine;
      use Data::Dumper;
      use Getopt::Long;

      GetOptions(
        "plugin=s" => \my @plugins
      );

      $SIG{INT} = sub { warn "SIGINT\n" };

      { package Data::Dumper; no strict 'vars';
        $Terse = $Indent = $Useqq = $Deparse = $Sortkeys = 1;
        $Quotekeys = 0;
      }

      my $eval = @plugins
       ? Eval::WithLexicals->with_plugins(@plugins)->new
       : Eval::WithLexicals->new;

      my $read = Term::ReadLine->new('Perl REPL');
      while (1) {
        my $line = $read->readline('re.pl$ ');
        exit unless defined $line;
        my @ret; eval {
          local $SIG{INT} = sub { die "Caught SIGINT" };
          @ret = $eval->eval($line); 1;
        } or @ret = ("Error!", $@);
        print Dumper @ret;
      }

      # shell session:

      $ perl -Ilib bin/tinyrepl 
      re.pl$ my $x = 0;
      0
      re.pl$ ++$x;
      1
      re.pl$ $x + 3;
      4
      re.pl$ ^D
      $

METHODS
  new
      my $eval = Eval::WithLexicals->new(
        lexicals => { '$x' => \1 },      # default {}
        in_package => 'PackageToEvalIn', # default Eval::WithLexicals::Scratchpad
        context => 'scalar',             # default 'list'
        prelude => 'use warnings',       # default 'use strictures 1'
      );

  eval
      my @return_value = $eval->eval($code_to_eval);

  lexicals
      my $current_lexicals = $eval->lexicals;

      $eval->lexicals(\%new_lexicals);

  in_package
      my $current_package = $eval->in_package;

      $eval->in_package($new_package);

  context
      my $current_context = $eval->context;

      $eval->context($new_context); # 'list', 'scalar' or 'void'

  prelude
    Code to run before evaling code. Loads strictures by default.

      my $current_prelude = $eval->prelude;

      $eval->prelude(q{use warnings}); # only warnings, not strict.

  with_plugins
      my $eval = Eval::WithLexicals->with_plugins("HintPersistence")->new;

    Construct a class with the given plugins. Plugins are roles located
    under a package name like "Eval::WithLexicals::With*".

    Current plugins are:

    *   HintPersistence

        When enabled this will persist pragams and other compile hints
        between evals (for example the strict and warnings flags in effect).
        See Eval::WithLexicals::WithHintPersistence for further details.

AUTHOR
    Matt S. Trout <mst@shadowcat.co.uk>

CONTRIBUTORS
    David Leadbeater <dgl@dgl.cx>

    haarg - Graham Knop (cpan:HAARG) <haarg@cpan.org>

COPYRIGHT
    Copyright (c) 2010 the Eval::WithLexicals "AUTHOR" and "CONTRIBUTORS" as
    listed above.

LICENSE
    This library is free software and may be distributed under the same
    terms as perl itself.