On Thu, Apr 21, 2005 at 12:09:18AM +0800, Autrijus Tang wrote: : Adding a special form Parens that takes one Exp and simply returns : it is possible, but unless it serves to disambiguate other cases, : that approach seems more heavy-handed to me.
As someone who is currently trying to write a perfect p5-to-p5 [sic] translator, you have to somehow remember the parens (and whitespace (and comments (and constant-folded subtrees))) to have a complete AST representation of the original text. Or maybe it should be called a CST instead of an AST in that case... Though remembering doesn't have to be the default. But I'd like to point out that adding such annotations to the AST after you've optimized parts of the tree away is much more difficult than reserving a spot for them in the first place. I speak from sad experience... :-) Larry
