Re: when $$s =~ m/\G.../gc is too verbose

[Anonymous Monk]

Maybe I don't understand the problem, but if you really hate typing so much, why not generalize the solution instead?

Not that I like to generalize things, because I usually end up un-generalizing them a few months later (stupid shifting requirements!), but it seems easier than playing with symbol table manipulations just to save a few keystrokes to me... am I missing something?

I'm thinking of something roughly along these lines... completely untested and possibly wrong code is below. ;-)

# make a table of regular expression patterns
my %table = ( qr/(\d+)/      => 'INT',
              qr/([A-Z]\w*)/ => 'ID',
              .... # more tokens here );
my ($parser) = shift;

my $s = $parser->YYData->{INPUT};

my @matches; # any matches found by our re go in here

foreach my $re ( keys %table ) {
        # for each regexp, check to see if it matches, and
        # put all the captured values in @matches if it does
        @matches = ( $$s =~ m/\G$re/gc );

       # return the appropriate token, and captures...
        return( $table{$re}, @matches) if (@matches);
} # end search for a token match

# token not found... put error handling here ...

--
Ytrew

[stefp]

Without going to the extremeties of toke.c (the Perl tokenizer), things are usally more complicated than mere pattern matching. One may have to test whatever flags. Otherwise, indeed one could factorize one way or another.