Text::RewriteRules 0.10

Text::RewriteRules Perl module contains a system to rewrite text using regexp-based rules.

SYNOPSIS

use Text::RewriteRules;

RULES email
.==> DOT
@==> AT
ENDRULES

email("ambs@cpan.org") # returns ambs AT cpan DOT org

RULES/m inc
(d+)=e=> $1+1
ENDRULE

inc("I saw 11 cats and 23 docs") # returns I saw 12 cats and 24 docs

ABSTRACT

This module uses a simplified syntax for regexp-based rules for rewriting text. You define a set of rules, and the system applies them until no more rule can be applied.

Two variants are provided:

traditional rewrite (RULES function):

while it is possible do substitute
| apply first substitution rule

cursor based rewrite (RULES/m function):

add a cursor to the begining of the string
while not reach end of string
| apply substitute just after cursor and advance cursor
| or advance cursor if no rule can be applied

A lot of computer science problems can be solved using rewriting rules.
Rewriting rules consist of mainly two parts: a regexp (LHS: Left Hand Side) that is matched with the text, and the string to use to substitute the content matched with the regexp (RHS: Right Hand Side).

Now, why dont use a simple substitute? Because we want to define a set of rules and match them again and again, until no more regexp of the LHS matches.

A point of discussion is the syntax to define this system. A brief discussion shown that some users would prefer a function to receive an hash with the rules, some other, prefer some syntax sugar.

The approach used is the last: we use Filter::Simple such that we can add a specific non-perl syntax inside the Perl script. This improves legibility of big rewriting rules sytems.

This documentation is divided in two parts: first we will see the reference of the module. Kind of, what it does, with a brief explanation. Follows a tutorial which will be growing through time and releases.