[TxMt] Re: Composable grammars

[Jacob Carlborg]

On 2016-04-10 16:43, Allan Odgaard wrote:

> Just to be sure I understand, you would like to define somewhere in the
> grammar how e.g. an identifier looks (regex) and then in other patterns,
> say a function prototype, be able to insert this definition (in the full
> regex for the function prototype)?

Kind of.

> If so, have a look at this proposal:
> https://github.com/textmate/textmate/pull/1276#issuecomment-63450941 and
> let me know if that fits your needs.

I've looked at that before. It's difficult to tell if it fits my needs 
without trying it.

It's question of how well it scales and how it's implement. I would 
prefer to define rules in the TextMate grammar that exactly matches the 
rules in the official grammar of a language. For that it would require 
many variables and many levels deep.

It will no work by just providing some syntax that allows to interpolate 
the regular expression. I tried that. I've even create a full Ruby DSL 
[1] to describe TextMate grammars. It worked great until TextMate choke 
on the generated regular expression being too long. I gave up when it 
took 15 seconds to load language.

Here's an example using that Ruby DSL to describe an integer literal 
[2]. That might give you and idea of what I'm after.

[1] https://github.com/jacob-carlborg/tm_grammar/tree/dev
[2] 
https://github.com/jacob-carlborg/d.tmbundle/blob/reboot_grammar/Syntaxes/rules/integer_literal.tm_lang.rb

-- 
/Jacob Carlborg