Add Houdini VEX language support

[igor-elovikov]

Support for VEX Language used in Houdini software: https://www.sidefx.com/docs/houdini/vex/lang.html
It's a very simple C-like shader language with couple of quirks

No LSP, only grammar: https://github.com/igor-elovikov/tree-sitter-vex and snippets for builtins (with help provided in tooltips)

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[igor-elovikov]

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[MrSubidubi]

Thanks for this and sorry for the way too long wait!

Could you please elaborate why the snippet file is that large - is this supposed to be a replacement for a proper language server?

Furthermore, could we update the language ID to houdini-vex to be a bit more descriptive? Thanks!

[igor-elovikov]

Thanks! no worries!

sorry, didn't quite get about language id, I've renamed extension id and language folder name. Language config has only the human readable name (I kept it as "VEX")

for snippets you're right and it mirrors actually how for example vscode extensions for vex authored (just providing snippets for builtins)
It's a bit niche language but it also has a lot of small quirks so you can't actually reuse any existing servers and nobody bothers writing one. VEX has a lot of builtins and it's very useful to autocomplete them with a bit of help. I just parse official specs and create snippets so I can see suggestions and small tooltips:

it does feel a little like exploiting snippets
if you fell this is not right I can remove it but it is useful and Houdini users already used to that