This document discusses using Perl to parse human language and summarize currency conversion queries. It provides examples of using regular expressions in Perl 5.10 and grammars in Perl 6 to parse currency queries, extract the currency codes and amounts, and return the conversion rate between currencies by accessing a hash of rates. Gearman is also mentioned as a way to distribute jobs across multiple worker processes to improve scalability.
44. say "OK";
my $value = $<rate_question><money><value> || 1;
my $from = $<rate_question><money><code>;
my $to = $<rate_question><currency_code> || 'EUR';
say "$value, $from -> $to";