[antlr-interest] Re: Anyone tried this ANTLR-inspired CC?

[Terence Parr]

On Monday, November 10, 2003, at 06:10 PM, micheal_jor wrote:

> --- In antlr-interest at yahoogroups.com, Terence Parr <parrt at c...> wrote:
>>
>> On Sunday, November 9, 2003, at 05:37 PM, leung13512c wrote:
>>
>>> The thing that caused me to switch away from ANTLR syntax
>>> is because I prefer the tree building syntax of JJTree that always
>>> create imaginary nodes instead of a mix of both.  And it mostly
>>> avoid having to create nodes within actions.
>>
>> Howdy.  This is the old AST versus parse tree argument...Parse trees
>> are easy to generate (i.e., no cost to developer) but have way too 
>> much
>> noise for tree transformation and also are sensitive to grammar
>> construction whereas ASTs are the canonical repr for a particular
>> language.
>
> Hmmm. If you are saying ANTLR generates a CST (aka. parse tree or
> concrete syntax tree) by default and the JJTree way is to generate an
> AST, you may be right Ter.

Actually, antlr likes ASTs not parse trees though you could of course 
build one.  In essence, I'm saying that ANTLR likes

   +
  /  \
3  4

for "3+4" without any rule nodes in there like a parse tree has.

Ter
--
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