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use v5.10;
use warnings;
# SHOWCASE VARIOUS ERROR MESSAGES WITH A VERY UNWELL GRAMMAR
use Parse::RecDescent;
open (Parse::RecDescent::ERROR, ">-") or die;
$grammar =
q{
<warn:3>
typedef : a ... ...! ... b
typedef : a ...!...!...!...! b
| /type/ ident /has/ field(s) /end type/
{ $result = $item[2]; }
| /type/ ident /is/ ident
{ $result = $item[2]; }
| quasit(s)
| quasit(-1..3)
| quasit(..0)
| field(?) field end
| <error> quasit "here" ...!/why/
Extend: extend
Replace: replace
$%^@#
field : /field/ ident /is/ ident
| field quasit
| !quasit(s?)
!| #NOTHING
typedef : whatever
package somewhereelse
!ident : /[A-Za-z]\w*???/
{ $result = $item[1]; }
quasit : field
| typedef
};
new Parse::RecDescent ($grammar) || die "Bad grammar! No biscuit!\n";
|
