[stringtemplate-interest] Re: [antlr-dev] ST output start/stop tags

[Terence Parr]

On Jun 14, 2006, at 12:25 AM, Jim Idle wrote:

> That would pretty much do it for me as I found that once I knew which
> template had spat out which piece of code, the rest was easy from  
> there.

Yeah, it works pretty well.

> On another note, there will be a need to spit out more than one  
> header file
> and perhaps extra C code (or other targets) for additionally  
> features I
> would like to add (such as perhaps auto generating a COM interface  
> or .Net
> or indeed anything at all really.

Crap...not sure how to handle that...i special case the .hpp file at  
this point.

> Do you have any strong preferences for the way to do this. My  
> thought is
> that the codegen target .java file could just call any additional  
> templates
> it wants when it is called to generate the header file and the  
> target file.

As long as we can agree on the data they need, and which template  
names, it should work fine.

> However, what method do you wish to adopt (as it should be  
> orthogonal across
> all codegens if possible) for signifying that 'extras' are  
> requested from
> codegen. I think that it should be some construct in the grammar,  
> and it
> probably isn't options. There could be new @ sections etc.

I like using the optional keyword:

optional
headerFile(LEXER, PARSER, TREE_PARSER, actionScope, actions, docComment,
            recognizer, name, tokens, tokenNames, scopes, rules,
	   cyclicDFADescriptors,
            bitsets, buildTemplate, profile, backtracking, synpreds,
            memoize, numRules, fileName, ANTLRVersion,  
generatedTimestamp);

Your Target.java file can ask if headerFile is there

> Before just making something up though, how about you suggest  
> something and
> unless I can find something wrong with it, I will just use it. So,  
> let's say
> that the C codegen has an option to produce an additional .c and .h  
> file for
> some option, such as foobar. What do you think?

Seems ok to me...Currently Target superclass has:

	protected void genRecognizerFile(Tool tool,
									CodeGenerator generator,
									Grammar grammar,
									StringTemplate outputFileST)
		throws IOException
	{
		String fileName = generator.getRecognizerFileName();
		generator.write(outputFileST, fileName);
	}

	protected void genRecognizerHeaderFile(Tool tool,
										   CodeGenerator generator,
										   Grammar grammar,
										   StringTemplate headerFileST)
		throws IOException
	{
		// no header file by default
	}

Perhaps we should call that 2nd one: genAncillaryFiles() or something.

Ter