Sub::HandlesVia::HandlerLibrary::String(3)

NAME
Sub::HandlesVia::HandlerLibrary::String - library of string-related methods

SYNOPSIS
  package My::Class {
    use Moo;
    use Sub::HandlesVia;
    use Types::Standard 'Str';
    has attr => (
      is => 'rwp',
      isa => Str,
      handles_via => 'String',
      handles => {
        'my_append' => 'append',
        'my_chomp' => 'chomp',
        'my_chop' => 'chop',
        'my_clear' => 'clear',
        'my_cmp' => 'cmp',
        'my_cmpi' => 'cmpi',
        'my_contains' => 'contains',
        'my_contains_i' => 'contains_i',
        'my_ends_with' => 'ends_with',
        'my_ends_with_i' => 'ends_with_i',
        'my_eq' => 'eq',
        'my_eqi' => 'eqi',
        'my_fc' => 'fc',
        'my_ge' => 'ge',
        'my_gei' => 'gei',
        'my_get' => 'get',
        'my_gt' => 'gt',
        'my_gti' => 'gti',
        'my_inc' => 'inc',
        'my_lc' => 'lc',
        'my_le' => 'le',
        'my_lei' => 'lei',
        'my_length' => 'length',
        'my_lt' => 'lt',
        'my_lti' => 'lti',
        'my_match' => 'match',
        'my_match_i' => 'match_i',
        'my_ne' => 'ne',
        'my_nei' => 'nei',
        'my_prepend' => 'prepend',
        'my_replace' => 'replace',
        'my_replace_globally' => 'replace_globally',
        'my_reset' => 'reset',
        'my_set' => 'set',
        'my_starts_with' => 'starts_with',
        'my_starts_with_i' => 'starts_with_i',
        'my_substr' => 'substr',
        'my_uc' => 'uc',
      },
    );
  }

DESCRIPTION
This is a library of methods for Sub::HandlesVia.

DELEGATABLE METHODS

  append( $tail )
Arguments: Str.

Appends another string to the end of the current string and updates the attribute.

  my $object = My::Class->new( attr => 'foo' );
  $object->my_append( 'bar' );
  say $object->attr; ## ==> 'foobar'

  chomp()
Like "chomp" from perlfunc.

  chop()
Like "chop" from perlfunc.

  clear()
Sets the string to the empty string.

  my $object = My::Class->new( attr => 'foo' );
  $object->my_clear;
  say $object->attr; ## nothing

  cmp( $str )
Arguments: Str.

Returns "$object->attr cmp $str".

  cmpi( $str )
Arguments: Str.

Returns "fc($object->attr) cmp fc($str)". Uses "lc" instead of "fc" in versions of Perl older than 5.16.

  contains( $str )
Arguments: Str.

Returns true iff the string contains $str.

  contains_i( $str )
Arguments: Str.

Returns true iff the string contains $str case-insensitvely.

  ends_with( $tail )
Arguments: Str.

Returns true iff the string ends with $tail.

  ends_with_i( $tail )
Arguments: Str.

Returns true iff the string ends with $tail case-insensitvely.

  eq( $str )
Arguments: Str.

Returns "$object->attr eq $str".

  eqi( $str )
Arguments: Str.

Returns "fc($object->attr) eq fc($str)". Uses "lc" instead of "fc" in versions of Perl older than 5.16.

  fc()
Returns fc($object->attr).

  ge( $str )
Arguments: Str.

Returns "$object->attr ge $str".

  gei( $str )
Arguments: Str.

Returns "fc($object->attr) ge fc($str)". Uses "lc" instead of "fc" in versions of Perl older than 5.16.

  get()
Gets the current value of the string.

  my $object = My::Class->new( attr => 'foo' );
  say $object->my_get; ## ==> 'foo'

  gt( $str )
Arguments: Str.

Returns "$object->attr gt $str".

  gti( $str )
Arguments: Str.

Returns "fc($object->attr) gt fc($str)". Uses "lc" instead of "fc" in versions of Perl older than 5.16.

  inc()
Performs "++" on the string.

  lc()
Returns lc($object->attr).

  le( $str )
Arguments: Str.

Returns "$object->attr le $str".

  lei( $str )
Arguments: Str.

Returns "fc($object->attr) le fc($str)". Uses "lc" instead of "fc" in versions of Perl older than 5.16.

  length()
Like "length" from perlfunc.

  my $object = My::Class->new( attr => 'foo' );
  say $object->my_length; ## ==> 3

  lt( $str )
Arguments: Str.

Returns "$object->attr lt $str".

  lti( $str )
Arguments: Str.

Returns "fc($object->attr) lt fc($str)". Uses "lc" instead of "fc" in versions of Perl older than 5.16.

  match( $regexp )
Arguments: Str|RegexpRef.

Returns true iff the string matches the regexp.

  my $object = My::Class->new( attr => 'foo' );
  if ( $object->my_match( '^f..$' ) ) {
    say 'matched!';
  }

  match_i( $regexp )
Arguments: Str|RegexpRef.

Returns true iff the string matches the regexp case-insensitively.

  my $object = My::Class->new( attr => 'foo' );
  if ( $object->my_match_i( '^F..$' ) ) {
    say 'matched!';
  }

  ne( $str )
Arguments: Str.

Returns "$object->attr ne $str".

  nei( $str )
Arguments: Str.

Returns "fc($object->attr) ne fc($str)". Uses "lc" instead of "fc" in versions of Perl older than 5.16.

  prepend( $head )
Arguments: Str.

Prepends another string to the start of the current string and updates the attribute.

  my $object = My::Class->new( attr => 'foo' );
  $object->my_prepend( 'bar' );
  say $object->attr; ## ==> 'barfoo'

  "replace( $regexp, $replacement )"
Arguments: Str|RegexpRef, Str|CodeRef.

Replaces the first regexp match within the string with the replacement string.

  my $object = My::Class->new( attr => 'foo' );
  $object->my_replace( 'o' => 'a' );
  say $object->attr; ## ==> 'fao'

  my $object2 = My::Class->new( attr => 'foo' );
  $object2->my_replace( qr/O/i => sub { return 'e' } );
  say $object2->attr; ## ==> 'feo'

  "replace_globally( $regexp, $replacement )"
Arguments: Str|RegexpRef, Str|CodeRef.

Replaces the all regexp matches within the string with the replacement string.

  my $object = My::Class->new( attr => 'foo' );
  $object->my_replace_globally( 'o' => 'a' );
  say $object->attr; ## ==> 'faa'

  my $object2 = My::Class->new( attr => 'foo' );
  $object2->my_replace_globally( qr/O/i => sub { return 'e' } );
  say $object2->attr; ## ==> 'fee'

  reset()
Resets the attribute to its default value, or an empty string if it has no default.

  set( $value )
Arguments: Str.

Sets the string to a new value.

  my $object = My::Class->new( attr => 'foo' );
  $object->my_set( 'bar' );
  say $object->attr; ## ==> 'bar'

  starts_with( $head )
Arguments: Str.

Returns true iff the string starts with $head.

  starts_with_i( $head )
Arguments: Str.

Returns true iff the string starts with $head case-insensitvely.

  "substr( $start, $length?, $replacement? )"
Arguments: Int, Optional[Int], Optional[Str].

Like "substr" from perlfunc, but is not an lvalue.

  uc()
Returns uc($object->attr).

EXTENDED EXAMPLES

  Using eq for Enum
  use strict;
  use warnings;

  package My::Person {
    use Moo;
    use Sub::HandlesVia;
    use Types::Standard qw( Str Enum );

    has name => (
      is => 'ro',
      isa => Str,
      required => 1,
    );

    has status => (
      is => 'rwp',
      isa => Enum[ 'alive', 'dead' ],
      handles_via => 'String',
      handles => {
        is_alive => [ eq  => 'alive' ],
        is_dead  => [ eq  => 'dead' ],
        kill     => [ set => 'dead' ],
      },
      default => 'alive',
    );

    # Note: method modifiers work on delegated methods
    #
    before kill => sub {
      my $self = shift;
      warn "overkill" if $self->is_dead;
    };
  }

  my $bob = My::Person->new( name => 'Robert' );
  say $bob->is_alive; ## ==> true
  say $bob->is_dead;  ## ==> false
  $bob->kill;
  say $bob->is_alive; ## ==> false
  say $bob->is_dead;  ## ==> true

See also Sub::HandlesVia::HandlerLibrary::Enum, MooX::Enumeration and MooseX::Enumeration.

  Match with curried regexp
  use strict;
  use warnings;

  package My::Component {
    use Moo;
    use Sub::HandlesVia;
    use Types::Standard qw( Str Int );

    has id => (
      is => 'ro',
      isa => Int,
      required => 1,
    );

    has name => (
      is => 'ro',
      isa => Str,
      required => 1,
      handles_via => 'String',
      handles => {
        name_is_safe_filename => [ match => qr/\A[A-Za-z0-9]+\z/ ],
        _lc_name => 'lc',
      },
    );

    sub config_filename {
      my $self = shift;
      if ( $self->name_is_safe_filename ) {
        return sprintf( '%s.ini', $self->_lc_name );
      }
      return sprintf( 'component-%d.ini', $self->id );
    }
  }

  my $foo = My::Component->new( id => 42, name => 'Foo' );
  say $foo->config_filename; ## ==> 'foo.ini'

  my $bar4 = My::Component->new( id => 99, name => 'Bar #4' );
  say $bar4->config_filename; ## ==> 'component-99.ini'

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

SEE ALSO
Sub::HandlesVia.

AUTHOR
Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE
This software is copyright (c) 2020, 2022 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.