use strict; use Parse::RecDescent; sub parse { my ($grammar, $str) = @_; open(*Parse::RecDescent::ERROR, '>', \my $error) or die "Cannot open in-memory filehandle: $!"; local $::RD_ERROR = 1; local $::RD_WARN = 2; my $p = Parse::RecDescent->new($grammar) or die "Grammar is invalid"; my $x = $p->start($str); defined $x or die "CAPTURED: $error"; return $x; } print parse('start: /foo/ | ', 'fo'), "\n";