Breaking The Rules II is of interest indeed.

My parser consists of a self made lexer and a recursive descending parser. The code is quite lengthy, but not really complicated.

Parsing and evaluation are different steps indeed, you can do something like 

use Data::Dumper;
my $m = Math::Light::Expression->new;
$m->parse($expression);
print Dumper $m->{ast};
for (0 .. 9) {
    print $val->({ a => $_ }), "\n"; # evaluate multiple times
}

[download]

I experimented with a LaTeX emitting backend, but that goes against the grain of keeping modules small and doing exactly what they are meant for.

I considered a PIR emitter as well, but PIR handles precedence on its on, so there is now real need to for my parser ;-)

Perl 6 in German

In reply to Re^2: RFC: Module for evaluation math. expressions by moritz
in thread RFC: Module for evaluation math. expressions by moritz

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