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Current Directory: /usr/share/doc/perl-Sub-Quote
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NAME
    Sub::Quote - Efficient generation of subroutines via string eval

SYNOPSIS
     package Silly;

     use Sub::Quote qw(quote_sub unquote_sub quoted_from_sub);

     quote_sub 'Silly::kitty', q{ print "meow" };

     quote_sub 'Silly::doggy', q{ print "woof" };

     my $sound = 0;

     quote_sub 'Silly::dagron',
       q{ print ++$sound % 2 ? 'burninate' : 'roar' },
       { '$sound' => \$sound };

    And elsewhere:

     Silly->kitty;  # meow
     Silly->doggy;  # woof
     Silly->dagron; # burninate
     Silly->dagron; # roar
     Silly->dagron; # burninate

DESCRIPTION
    This package provides performant ways to generate subroutines from
    strings.

SUBROUTINES
  quote_sub
     my $coderef = quote_sub 'Foo::bar', q{ print $x++ . "\n" }, { '$x' => \0 };

    Arguments: ?$name, $code, ?\%captures, ?\%options

    $name is the subroutine where the coderef will be installed.

    $code is a string that will be turned into code.

    "\%captures" is a hashref of variables that will be made available to
    the code. The keys should be the full name of the variable to be made
    available, including the sigil. The values should be references to the
    values. The variables will contain copies of the values. See the
    "SYNOPSIS"'s "Silly::dagron" for an example using captures.

    Exported by default.

   options
    "no_install"
      Boolean. Set this option to not install the generated coderef into the
      passed subroutine name on undefer.

    "no_defer"
      Boolean. Prevents a Sub::Defer wrapper from being generated for the
      quoted sub. If the sub will most likely be called at some point,
      setting this is a good idea. For a sub that will most likely be
      inlined, it is not recommended.

    "package"
      The package that the quoted sub will be evaluated in. If not
      specified, the package from sub calling "quote_sub" will be used.

    "hints"
      The value of $^H to use for the code being evaluated. This captures
      the settings of the strict pragma. If not specified, the value from
      the calling code will be used.

    "warning_bits"
      The value of "${^WARNING_BITS}" to use for the code being evaluated.
      This captures the warnings set. If not specified, the warnings from
      the calling code will be used.

    "%^H"
      The value of "%^H" to use for the code being evaluated. This captures
      additional pragma settings. If not specified, the value from the
      calling code will be used if possible (on perl 5.10+).

    "attributes"
      The "Subroutine Attributes" in perlsub to apply to the sub generated.
      Should be specified as an array reference. The attributes will be
      applied to both the generated sub and the deferred wrapper, if one is
      used.

    "file"
      The apparent filename to use for the code being evaluated.

    "line"
      The apparent line number to use for the code being evaluated.

  unquote_sub
     my $coderef = unquote_sub $sub;

    Forcibly replace subroutine with actual code.

    If $sub is not a quoted sub, this is a no-op.

    Exported by default.

  quoted_from_sub
     my $data = quoted_from_sub $sub;

     my ($name, $code, $captures, $compiled_sub) = @$data;

    Returns original arguments to quote_sub, plus the compiled version if
    this sub has already been unquoted.

    Note that $sub can be either the original quoted version or the compiled
    version for convenience.

    Exported by default.

  inlinify
     my $prelude = capture_unroll '$captures', {
       '$x' => 1,
       '$y' => 2,
     }, 4;

     my $inlined_code = inlinify q{
       my ($x, $y) = @_;

       print $x + $y . "\n";
     }, '$x, $y', $prelude;

    Takes a string of code, a string of arguments, a string of code which
    acts as a "prelude", and a Boolean representing whether or not to
    localize the arguments.

  quotify
     my $quoted_value = quotify $value;

    Quotes a single (non-reference) scalar value for use in a code string.
    Numbers aren't treated specially and will be quoted as strings, but
    undef will quoted as "undef()".

  capture_unroll
     my $prelude = capture_unroll '$captures', {
       '$x' => 1,
       '$y' => 2,
     }, 4;

    Arguments: $from, \%captures, $indent

    Generates a snippet of code which is suitable to be used as a prelude
    for "inlinify". $from is a string will be used as a hashref in the
    resulting code. The keys of %captures are the names of the variables and
    the values are ignored. $indent is the number of spaces to indent the
    result by.

  qsub
     my $hash = {
      coderef => qsub q{ print "hello"; },
      other   => 5,
     };

    Arguments: $code

    Works exactly like "quote_sub", but includes a prototype to only accept
    a single parameter. This makes it easier to include in hash structures
    or lists.

    Exported by default.

  sanitize_identifier
     my $var_name = '$variable_for_' . sanitize_identifier('@name');
     quote_sub qq{ print \$${var_name} }, { $var_name => \$value };

    Arguments: $identifier

    Sanitizes a value so that it can be used in an identifier.

ENVIRONMENT
  SUB_QUOTE_DEBUG
    Causes code to be output to "STDERR" before being evaled. Several forms
    are supported:

    1   All subs will be output.

    "/foo/"
        Subs will be output if their code matches the given regular
        expression.

    "simple_identifier"
        Any sub with the given name will be output.

    "Full::identifier"
        A sub matching the full name will be output.

    "Package::Name::"
        Any sub in the given package (including anonymous subs) will be
        output.

CAVEATS
    Much of this is just string-based code-generation, and as a result, a
    few caveats apply.

  return
    Calling "return" from a quote_sub'ed sub will not likely do what you
    intend. Instead of returning from the code you defined in "quote_sub",
    it will return from the overall function it is composited into.

    So when you pass in:

       quote_sub q{  return 1 if $condition; $morecode }

    It might turn up in the intended context as follows:

      sub foo {

        <important code a>
        do {
          return 1 if $condition;
          $morecode
        };
        <important code b>

      }

    Which will obviously return from foo, when all you meant to do was
    return from the code context in quote_sub and proceed with running
    important code b.

  pragmas
    "Sub::Quote" preserves the environment of the code creating the quoted
    subs. This includes the package, strict, warnings, and any other lexical
    pragmas. This is done by prefixing the code with a block that sets up a
    matching environment. When inlining "Sub::Quote" subs, care should be
    taken that user pragmas won't effect the rest of the code.

SUPPORT
    Users' IRC: #moose on irc.perl.org

    Development and contribution IRC: #web-simple on irc.perl.org

    Bugtracker:
    <https://rt.cpan.org/Public/Dist/Display.html?Name=Sub-Quote>

    Git repository: <git://github.com/moose/Sub-Quote.git>

    Git browser: <https://github.com/moose/Sub-Quote>

AUTHOR
    mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk>

CONTRIBUTORS
    frew - Arthur Axel "fREW" Schmidt (cpan:FREW) <frioux@gmail.com>

    ribasushi - Peter Rabbitson (cpan:RIBASUSHI) <ribasushi@cpan.org>

    Mithaldu - Christian Walde (cpan:MITHALDU)
    <walde.christian@googlemail.com>

    tobyink - Toby Inkster (cpan:TOBYINK) <tobyink@cpan.org>

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

    bluefeet - Aran Deltac (cpan:BLUEFEET) <bluefeet@gmail.com>

    ether - Karen Etheridge (cpan:ETHER) <ether@cpan.org>

    dolmen - Olivier Mengué (cpan:DOLMEN) <dolmen@cpan.org>

    alexbio - Alessandro Ghedini (cpan:ALEXBIO) <alexbio@cpan.org>

    getty - Torsten Raudssus (cpan:GETTY) <torsten@raudss.us>

    arcanez - Justin Hunter (cpan:ARCANEZ) <justin.d.hunter@gmail.com>

    kanashiro - Lucas Kanashiro (cpan:KANASHIRO)
    <kanashiro.duarte@gmail.com>

    djerius - Diab Jerius (cpan:DJERIUS) <djerius@cfa.harvard.edu>

COPYRIGHT
    Copyright (c) 2010-2016 the Sub::Quote "AUTHOR" and "CONTRIBUTORS" as
    listed above.

LICENSE
    This library is free software and may be distributed under the same
    terms as perl itself. See <http://dev.perl.org/licenses/>.
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