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Keyword-With-0.003
River stage zero No dependents
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/ Keyword::With

NAME

Keyword::With - provide new syntax to use a 'given' statement without an experimental warning

VERSION

version 0.003

DESCRIPTION

Provide a construct almost identical to `given (...) { }` that evaluates an list expression in scalar context (assigning it to `$_`) then executing a block of code.

NAME

Keyword::With

SYNOPSIS

 use Keyword::With; 

 with (5*3) {
     print; 
 }

or

 with ( some_func() ) {
     print "matches\n" if grep { m/$_/ } qr/abc/, qr/def/;
     print "does not match\n"; 
 }

ADVANTAGES

No experimental warning

DISADVANTAGES

Cannot use builtins that modify `$_` with with blocks because they will clobber the `$_` value set by `with (...) { }`. This was already a disadvantage of given blocks. A reasonable approach would be to create a new lexical variable within the `with` block:

 with ( [qw(1 2 3 5 8 13 21)] ) {
     my @first_7_fibs = @$_;
     my @new_first_7_fibs = map { $_ + 1 } @first_7_fibs;
     ...
 }

AUTHOR

Hunter McMillen <mcmillhj@gmail.com>

COPYRIGHT AND LICENSE

This software is copyright (c) 2016 by Hunter McMillen.

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