Simple Helper to Extract Values from a String(laktek.com)

    expr     ::= sum
    sum      ::= product { ("+" | "-") product }
    product  ::= power   { ("*" | "/") power }
    power    ::= factor  [ "^" factor ]
    factor   ::= "(" expr ")" | variable | constant
    variable ::= identifier
    constant ::= floatLiteral

    def expr     = sum
    def sum      = product ~ rep(("+" | "-") ~ product)
    def product  = power   ~ rep(("*" | "/") ~ power)
    def power    = factor  ~ opt("^" ~ factor)
    def factor   = "(" ~ expr ~ ")" | variable | constant
    def variable = ident    
    def constant = floatLit 

    integer = Word( nums ) 
    variable = Word( alphas, max=1 )
    arithOp = Word( "+-*/", max=1 )
    equation = variable + "=" + integer + arithOp + integer

      extractValues('John Doe <[email protected]> (http://example.com)', '{name} <{email}> ({url})')
    >> {'name': 'John Doe', 'email': '[email protected]', 'url': 'http://example.com' }

    str = "2012-10-04T07:20:00"

    str =~ /
        (\d{4}) # four digit year
        -
        (\d{2}) # two digit month
        -
        (\d{2}) # two digit day
        T
        (\d{2}) # two digit hour
        :
        (\d{2}) # two digit min
        :
        (\d{2}) # two digit sec
       /x

    #!/usr/bin/env perl
     
    use Template::Extract;
    use Data::Printer;
     
    sub extractValues {
        my ($document, $template, $opts) = @_;
     
        my $delims = $opts->{delimiters} || [ qw/ { } / ];
        $document = lc $document
            if $opts->{lowercase};
        if (exists $opts->{whitespace}) {
            my $ws = ' ' x $opts->{whitespace};
            $document =~ s/\s+/$ws/g;
        }
        Template::Extract->new( { START_TAG => $delims->[0], END_TAG => $delims->[1] } )
                         ->extract( $template, $document );
    }
     
    p extractValues('/2012/08/12/test.html', '/{year}/{month}/{day}/{title}.html');
     
    p extractValues('John Doe <[email protected]> (http://example.com)', '{name} <{email}> ({url})');
     
    p extractValues('from 4th October  to 10th  October',
                      'from `from` to `to`',
                      { whitespace => 1, delimiters => ['`', '`'] });
     

    \ {
        day   12,
        month   08,
        title   "test",
        year   2012
    }
    \ {
        email   "[email protected]",
        name   "John Doe",
        url   "http://example.com"
    }
    \ {
        from   "4th October",
        to   "10th  October"
    }