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#! /usr/local/bin/perl -sw
# THE OL' "EMPTY SUBCLASS IN THE DEMO" TRICK.
use Parse::RecDescent;
sub Parse::RecDescent::f
{
print "Parse::RecDescent::f\n";
}
@DerParser::ISA = qw { Parse::RecDescent };
$grammar =
q{
typedef : /type/ ident /has/ <commit> field(s) 'end type'
{ $return = $item[2]; }
| /type/ ident ( /is/ | /are/ ) ident
{ $return = $item[2]; }
| <error>
field : /field/ ident /is/ ident
ident : /[A-Za-z]\w*/
{ f(); $return = $item[1]; }
};
$parse = new DerParser ( $grammar ) || die "\n";
$str = "
type student has
field name is text
field age
end type
";
print "> ", $parse->typedef($str) || "<failed (as expected)>", "\n";
$str = " type student has end type ";
print "> ", $parse->typedef($str) || "<failed (as expected)>", "\n";
$str = " type studentRec is student ";
print "> ", $parse->typedef($str) || "<failed (unexpectedly!)>", "\n";
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