[antlr-interest] Newbie Needs help...

[Nikolas Everett]

I haven't gotten that deep into this as of yet, but the idea is to have
something like
class VerificationCallback {
 private final List<Error> errors;

 public void import(ASTNode importedPackage) {//Do some checks, and add
errors to the list of errors}
  public void referencedType(ASTNode nodeForType) {//Do some checks, and add
errors to the list of errors}

}

You'd create the grammar with a member for the callback, and then you'd call
it when processing the tree like so:
import:  ^(IMPORT name=packageName) {this.callback.import(name);}

--Nik

On Wed, May 21, 2008 at 10:13 AM, Kevina Choolhun <kevina.choolhun at gmail.com>
wrote:

> Hello,
>
> Thanks! Could you please explain further what you mean by
>
> "1 grammar to verify the AST (tree grammar with no output, only embedded
> actions calling a callback)"
>
> Maybe, you mean error messages?
>
> Thank you.
>
> Kevina
>
>
> On Wed, May 21, 2008 at 5:59 PM, Nikolas Everett <nik9000 at gmail.com>
> wrote:
>
>> I learned a good portion of what I know about antlr and stringtemplate by
>> going through the source code for the Mantra compiler.  Its all here:
>> http://www.linguamantra.org/
>>
>> The long and short of it is that embedding actions is great for checking
>> things but is more cumbersome when actually generating output.  Tree
>> grammars that output templates are the way to go there.
>>
>> I tend to do:
>> 1 grammar to lex and parse into an AST (output=AST)
>> 1 grammar to verify the AST (tree grammar with no output, only embedded
>> actions calling a callback)
>> 1 grammar to generate output (tree grammar with output=template)
>>
>> This is wonderfully flexible because the grammars become modules, allowing
>> you to test them individually and substitute them at will.  This is kind of
>> a pain because you need to wrote three or more grammars and sync up the
>> output of the tree constructing grammar to the input of the others.
>>
>>
>> On Wed, May 21, 2008 at 9:45 AM, csanders <csanders at hoovers.com> wrote:
>>
>>> I'm also new to ANTLR and would like to know how StringTemplate is a
>>> better solution, is there somewhere we can read about this ?
>>>
>>> Thanks,
>>> Charlie
>>>
>>> Kevina Choolhun wrote:
>>>
>>>> Hello,
>>>>
>>>> I am new at ANTLR but with the help of The Definitive ANTLR Reference
>>>> have managed to set up a parser and a parser walker..
>>>>
>>>> Now for the next stage, I have tried my hand at embedding actions.. but
>>>> Stringtemplate I hear is a much better solution.
>>>>
>>>> I am currently reading through stringtemplate.org <
>>>> http://stringtemplate.org>. I wanted to know if there are any nice
>>>> tutorials about it which could help me.. enhance my parser n lexer with
>>>> StringTemplate
>>>>
>>>> Thank you for your help.
>>>>
>>>> --
>>>> Kev
>>>>
>>>
>>>
>>
>
>
> --
> Kevina
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