[antlr-interest] CommonTree & Tree grammar versus DIY

[Andy Tripp]

Marc,
This "writing by hand" article is referring to walking a tree-like data structure (the AST).
Pretty much every programmer already knows how to do this by hand:

void walk(Tree t) {
  doSomething(t);
  for (Tree child: t.children()) {
     walk(child);
  }
}

By contrast, there are only a handful of people who know how to do that same thing
with an ANTLR treewalker.

The "manipulating an AST" work of building a translator is quite a different
job than the "build a lexer/parser" part of it.

Andy

Marc Bischof wrote:
> Hello Andy,
> 
> in your article you wrote:
> 
>> I think the approach that you'll prefer depends on your background. If you're 
>> already intimately familiar with the ":", "[". "]", "*" , "{", "}", and ";" 
>> constructs in the first approach, you will prefer the terse approach. On    
>> the other hand, if you don't want to be bothered with all that "extra      
>> syntax", you'll prefer the more verbose "plain Java" approach. 
> 
> I think, if someone is not familiar with grammar stuff and has not the 
> background for writing translators, the last thing he/she should do is 
> writing it by hand.
> ...may be to get familiar with it, but not for a productive solution.
> 
> Cheers Marc
>