Problem with g:vimtex_syntax_alpha

[jubnzv]

Hi,

I found a small issue when updating vimtex to the latest version from git master.
It seems that f72642c leads to errors at startup.

Here are the error messages that appears when starting vim:

Error detected while processing /home/jubnzv/.local/share/nvim/plugged/vimtex/syntax/tex.vim:             
line   23:                                                                                                
E121: Undefined variable: g:vimtex_syntax_alpha                                                           
E15: Invalid expression: exists('b:current_syntax') || !g:vimtex_syntax_alpha                             
Error detected while processing /home/jubnzv/.local/share/nvim/plugged/vimtex/after/syntax/tex.vim:       
line    7:                                                                                                
E121: Undefined variable: g:vimtex_syntax_alpha                                                           
E15: Invalid expression: !g:vimtex_syntax_alpha   

It seems that the problem in the global variable g:vimtex_syntax_alpha.

If we replace g:vimtex_syntax_alpha to get(g:, 'vimtex_syntax_alpha') here and here, the plugin works as expected.

[lervag]

That's strange. This should'nt happen, because g:vimtex_syntax_alpha should be initialized before the syntax scripts. Can you give me a minimal vimrc for this?

[lervag]

It seems it is due to the order of syntax on vs. filetype plugin on. You should put filetype plugin on before syntax on.

[lervag]

I can't find a good source for this, but IMHO it is a standard best practise, and I think all of the plugin managers (like vim-plug) that automatically applies filetype plugin on and syntax on apply the operations in this order. Still, I think you raise an important issue, and before I "insist" that people put things in a given order I will accept your suggested change.

In the future, I might want to specify a correct order so that the syntax scripts may rely on the filetype plugin state. This is actually already assumed for certain syntax elements, so if you want things to work correctly, you should already now update your vimrc as I've mentioned.

[jubnzv]

@lervag thank you for looking this.

It seems that the vim-plug doesn't set this option. They only set filetype plugin indent on here.

[lervag]

@lervag thank you for looking this.

No problem.

It seems that the vim-plug doesn't set this option. They only set filetype plugin indent on here.

But, I'm sorry, but you're wrong. And you're staring right at it. The code does exactly what I was talking about. See also this excerpt from the docs of vim-plug:

 3. `call plug#end()` to update 'runtimepath' and initialize plugin system
   - Automatically executes `filetype plugin indent on` and `syntax enable`.
     You can revert the settings after the call. e.g. `filetype indent off`,
     `syntax off`, etc.

Note: filetype plugin on and filetype plugin indent on is "the same", except filetype plugin indent on also enables the indent scripts. syntax enable is similar to syntax on. For more info, read the docs, e.g. :help :filetype and :help :syn-enable.

[jubnzv]

Oh, got it. Thank you for the clarification.

The behavior of filetype functions is more clearly visible in the source code: ex_filetype. The plugin and indent options are treated as arguments for the filetype command here.

[lervag]

Oh, got it. Thank you for the clarification.

No problem!

The behavior of filetype functions is more clearly visible in the source code: ex_filetype. The plugin and indent options are treated as arguments for the filetype command here.

I've not really looked much at the Vim source code, and I've not very much experience with C. But yes, that was not so hard to read. :)