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Data-Object-0.07
River stage one • 1 direct dependent • 1 total dependent
13 ++
/ Data::Object::Code

NAME

Data::Object::Code - A Code Object for Perl 5

VERSION

version 0.07

SYNOPSIS

    use Data::Object::Code;

    my $code = Data::Object::Code->new(sub { shift + 1 });

DESCRIPTION

Data::Object::Code provides common methods for operating on Perl 5 code references. Code methods work on code references.

CODIFICATION

Certain methods provided by the this module support codification, a process which converts a string argument into code reference which can be used to supply a callback to the routine. Codified strings can access its arguments by using variable names which correspond to letters in the alphabet which represent the position in the argument list. For example:

    $hash->method('$a + $b * $c', 100);

    # given that $a and $b are method-supplied arguments
    # ... whereas $c is assigned the user-supplied argument, 25

METHODS

call

    # given sub { (shift // 0) + 1 }

    $code->call; # 1
    $code->call(0); # 1
    $code->call(1); # 2
    $code->call(2); # 3

The call method executes and returns the result of the code. This method returns a data type object to be determined after execution.

compose

    # given sub { [@_] }

    $code = $code->compose($code, 1,2,3);
    $code->(4,5,6); # [[1,2,3,4,5,6]]

    # this can be confusing, here's what's really happening:
    my $listing = sub {[@_]}; # produces an arrayref of args
    $listing->($listing->(@args)); # produces a listing within a listing
    [[@args]] # the result

The compose method creates a code reference which executes the first argument (another code reference) using the result from executing the code as it's argument, and returns a code reference which executes the created code reference passing it the remaining arguments when executed. This method returns a Data::Object::Code object.

conjoin

    # given sub { $_[0] % 2 }

    $code = $code->conjoin(sub { 1 });
    $code->(0); # 0
    $code->(1); # 1
    $code->(2); # 0
    $code->(3); # 1
    $code->(4); # 0

The conjoin method creates a code reference which execute the code and the argument in a logical AND operation having the code as the lvalue and the argument as the rvalue. This method returns a Data::Object::Code object.

curry

    # given sub { [@_] }

    $code = $code->curry(1,2,3);
    $code->(4,5,6); # [1,2,3,4,5,6]

The curry method returns a code reference which executes the code passing it the arguments and any additional parameters when executed. This method returns a Data::Object::Code object.

disjoin

    # given sub { $_[0] % 2 }

    $code = $code->disjoin(sub { -1 });
    $code->(0); # -1
    $code->(1); #  1
    $code->(2); # -1
    $code->(3); #  1
    $code->(4); # -1

The disjoin method creates a code reference which execute the code and the argument in a logical OR operation having the code as the lvalue and the argument as the rvalue. This method returns a Data::Object::Code object.

next

    $code->next;

The next method is an alias to the call method. The naming is especially useful (i.e. helps with readability) when used with closure-based iterators. This method returns a Data::Object::Code object. This method is an alias to the call method.

rcurry

    # given sub { [@_] }

    $code = $code->rcurry(1,2,3);
    $code->(4,5,6); # [4,5,6,1,2,3]

The rcurry method returns a code reference which executes the code passing it the any additional parameters and any arguments when executed. This method returns a Data::Object::Code object.

SEE ALSO

AUTHOR

Al Newkirk <anewkirk@ana.io>

COPYRIGHT AND LICENSE

This software is copyright (c) 2014 by Al Newkirk.

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