Improved support for sub-/superscript

[bnord01]

Description

It would be nice to have improved support for sub-/superscripts. Things I'm missing most from other editors like auctex:

1. Automatic insertion of {} after typing ^/_ (and placing the cursor inside)
2. Styling of _{}, ^{} (e.g. using vertical-align: sub/super and font-size: smaller)

Additional Information

Code Version 1.24.1
LaTeX Workshop Version 5.5.1
macOS

[jlelong]

1. Not all users would like to automatically insert {} after ^ / _, but there are two snippets to achieve this: __ (double underscore) + TAB inserts _{} with the cursor inside the brackets, ** + TAB inserts ^{}.
2. Syntax files only assign scopes. Then, themes are responsible for highlighting scopes. I have not found any themes with the ability to render sub/superscript are auctex does.

[bnord01]

Thanks, __ works quite well but I have to manually trigger completion for **. I'll investigate if I find any good option to render sub/superscripts.

[jlelong]

You are right ** does not trigger completion automatically, but hitting TAB converts ** into ^{} without triggering the completion list. Maybe, I have a specific completion setting. Can you check if it works like on your installation?

Any suggestion/help on the rendering of sub/superscripts is welcome. An other difficulty is that it is not possible to change syntax highlighting based on configuration variable. This means that the user could not choose if he wants to keep the current rendering of sub/superscripts or to use the auctex style.

[bnord01]

Typing **TAB leaves me with **TAB in the editor. I haven't made any changes to any completion settings.

[jlelong]

I will investigate this. Meanwhile, you can change the ** combination in the file snippets/latex.json by something else, for instance ^^ if ^ is not a dead key.

[jlelong]

@bnord01, can you give me your vscode user settings file as a gist to help me understand what is going on?

[bnord01]

@jlelong my user settings are empty and my workspace settings are here nothing that should really matter. Tested this under Windows 10 1709, VSCode 1.24.1 with LaTeX Workbench 5.5.1 and Spell Right 2.5.2 installed. (Edit: Same behaviour under macOS with the same versions.)

[bnord01]

As a followup, I tried actually using __ and quickly noticed, that this doesn't work in practice as almost always you'll be using this like x_ and the completion for __ won't match with the leading x.

[jlelong]

You need to set "editor.tabCompletion": true to make the snippets __ and ** work when they are glued to a leading expression.

[jlelong]

Everything should be properly fixed now. To have intellisense automatically triggered inside snippets, set "editor.suggest.snippetsPreventQuickSuggestions": false.