Parsing/Shunting-yard algorithm: Difference between revisions
→{{header|Raku}}
m (→{{header|Phix}}: syntax coloured) |
|||
Line 4,087:
=={{header|Raku}}==
(formerly Perl 6)
<lang perl6>
my %prec =
'^' => 4,
'*' => 3,
Line 4,094 ⟶ 4,095:
'-' => 2,
'(' => 1;
my %assoc =
'^' => 'right',
'*' => 'left',
Line 4,101 ⟶ 4,102:
'+' => 'left',
'-' => 'left';
sub shunting-yard ($prog) {
my @inp = $prog.words;
my @ops;
my @res;
sub report($op) { printf "%25s %-7s %10s %s\n", ~@res, ~@ops, $op, ~@inp }
sub shift($t) { report( "shift $t"); @ops.push: $t }
sub reduce($t) { report("reduce $t"); @res.push: $t }
while @inp {
}
}
▲ }
}
reduce @ops.pop while @ops;
@res;
}
say shunting-yard '3 + 4 * 2 / ( 1 - 5 ) ^ 2 ^ 3';
</lang>
{{out}}
<pre> reduce 3 + 4 * 2 / ( 1 - 5 ) ^ 2 ^ 3
| |||