Re: The craziest RegExes you ever created

[zshzn]

This is a very silly script I wrote to demonstrate the very possibility of how something could be done this way. The regex is to convert roman numerals to integers. It is neither useful nor witty.

use strict;

sub l { return length shift }
sub roman2int {
    $_ = shift;
    /(M*)(?{$a+=1000*l$1})(D*)(?:(?!M)(?{$a+=500*l$2})|(?{$a-=500*l$2}
+))(C*)(?:(?![MD])(?{$a+=100*l$3})|(?{$a-=100*l$3}))(L*)(?:(?![MDC])(?
+{$a+=50*l$4})|(?{$a-=50*l$4}))(X*)(?:(?![MDCL])(?{$a+=10*l$5})|(?{$a-
+=10*l$5}))(V*)(?:(?![MDCLX])(?{$a+=5*l$6})|(?{$a-=5*l$6}))(I*)(?:(?![
+MDCLXV])(?{$a+=1*l$7})|(?{$a-=1*l$7}))(M*)(?{$a+=1000*l$8})(D*)(?{$a+
+=500*l$9})(C*)(?:(?![MD])(?{$a+=100*l$10})|(?{$a-=100*l$10}))(L*)(?:(
+?![MDC])(?{$a+=50*l$11})|(?{$a-=50*l$11}))(X*)(?:(?![MDCL])(?{$a+=10*
+l$12})|(?{$a-=10*l$12}))(V*)(?:(?![MDCLX])(?{$a+=5*l$13})|(?{$a-=5*l$
+13}))(I*)(?:(?![MDCLXV])(?{$a+=1*l$14})|(?{$a-=1*l$14}))(C*)(?{$a+=10
+0*l$15})(L*)(?:(?![MDC])(?{$a+=50*l$16})|(?{$a-=50*l$16}))(X*)(?:(?![
+MDCL])(?{$a+=10*l$17})|(?{$a-=10*l$17}))(V*)(?:(?![MDCLX])(?{$a+=5*l$
+18})|(?{$a-=5*l$18}))(I*)(?:(?![MDCLXV])(?{$a+=1*l$19})|(?{$a-=1*l$19
+}))(L*)(?{$a+=100*l$20})(X*)(?:(?![MDCL])(?{$a+=10*l$21})|(?{$a-=10*l
+$21}))(V*)(?:(?![MDCLX])(?{$a+=5*l$22})|(?{$a-=5*l$22}))(I*)(?:(?![MD
+CLXV])(?{$a+=1*l$23})|(?{$a-=1*l$23}))(X*)(?{$a+=10*l$24})(V*)(?:(?![
+MDCLX])(?{$a+=5*l$25})|(?{$a-=5*l$25}))(I*)(?:(?![MDCLXV])(?{$a+=1*l$
+26})|(?{$a-=1*l$26}))(X*)(?{$a+=10*l$27})/;
    return $a;
}
print roman2int shift;

[Ieronim]

It is neither useful nor witty.

So i won't add it to my list, in spite of its incredible length :)

[zshzn]

Although it is both crazy and interesting, in its own way, and those were two attributes you requested :)