That's not completely true though; most of those analyses take the conclusion way past the point where it's accurate. You cannot definitively produce a single

That's not completely true though; most of those analyses take the conclusion way past the point where it's accurate. You cannot definitively produce a single canonical parse tree for every valid Perl 5 program without executing code in some cases, but you can produce a coherent and accurate parse tree without executing code if you allow nodes in the parse tree which express the two types of ambiguity (undeclared bareword interpretation and unknown arity). Most of the time this doesn't come up.