GrammarConsumptionExample3

gce3.raku

use Grammar::Tracer;

grammar Timestamp {
    token TOP{^<y><m><d>T<hr><mn>$}
    token y  {\d**4}
    token m  {\d**2}
    token d  {\d**2}
    token hr {\d**2}
    token mn {\d**2}
}
#say Timestamp.parse: '20130304T0102';

my $ts-match;

grammar TimestampedFile {
    token TOP{^<name> '-' <timestamp> '.' <ext>$}

    token name{<[a..z]>+}

    token timestamp { 
        \w+ <?{$ts-match = Timestamp.parse("$/")}> 
    }   

    token ext{<[a..z]>**3}
}

class TimestampedFileActions {
    method timestamp($/) {
        make $ts-match
    }   
}

my $res = TimestampedFile.parse('xxx-20130304T0102.csv', actions => TimestampedFileActions.new);
say ~$res<timestamp>.made<y>;