tutorial/regex2/add.p6
use v6;
BEGIN {
@*INC.push('examples/regex2/');
}
use Add1;
my @experssions = (
"2 + 3",
"2 + 4 ",
"2 + 3 x",
"2 +",
"2 3",
"2 - 3",
);
for @experssions -> $exp {
print $exp, " ";
my $result = Add1.parse($exp);
say $result ?? 'OK' !! 'NOT OK';
CATCH {
say "exception received: $!";
}
}
tutorial/regex2/Add1.pm
grammar Add1 {
rule TOP { ^ <math> $ }
rule math { <operand> <operator> <operand> }
token operand { \d+ }
token operator { <[\+\*]> }
}
tutorial/regex2/Add1.pm.out
2 + 3 OK 2 + 4 OK 2 + 3 x NOT OK 2 + NOT OK 2 3 NOT OK 2 - 3 NOT OK
Published on 2012-01-01