Snippets with prefix with no alpha-nunmeric character have inconsistent behavior

[jlelong]

Consider the following snippets (they are related to LaTeX but can be tested with plain text document)

"subscript": {
	"prefix": "__",
	"body": "_{$0}",
	"description": "Add a subscript"
},
"superscript": {
	"prefix": "**",
	"body": "^{$0}",
	"description": "Add a superscript"
},
"alpha": {
	"prefix": "@a",
	"body": "\\alpha",
	"description": "Insert alpha"
},
"partial": {
	"prefix": "@6",
	"body": "\\partial",
	"description": "Insert partial derivative symbol"
}

The prefix __ does automatically trigger intellisense but ** does not. For **, I have to manually trigger suggestions. Hitting TAB directly after **, without manually triggering suggestions just inserts some spaces.

Then, trying to complete b__ and b** leads to different behaviors

Similarly, The prefix @a triggers intellisense but @6requires manual triggering to show the suggestion menu. However, hitting TAB after @6 expands it even no suggestion shows up. This is not coherent with the behavior for **.

• VSCode Version: 1.29.1
• OS Version: macOS 10.14.1

Does this issue occur when all extensions are disabled?: Yes

[jrieken]

/duplicate of #62906 (comment)

[vscodebot]

Thanks for creating this issue! We figured it's covering the same as another one we already have. Thus, we closed this one as a duplicate. You can search for existing issues here. See also our issue reporting guidelines.

Happy Coding!

[jlelong]

@jrieken While googling I had come across #62906, which only explains why ** does not automatically trigger 24x7 intellisense. Does this also mean that @6 is not considered an end of word whereas @a is?

Moreover it does not explain why trying to complete b__ and b** leads to different behaviors


Note that in both screenshots, intellisense was triggered manually. This is actually the most annoying problem in my issue and it used to work.

[jrieken]

Each language defines what a word is - so it depends on that. We have this restriction because we don't want IntelliSense to constantly pop up.

[Astrantia]

@jrieken Can you point to the documentation about how to define words in languages?

[jrieken]

there you go: https://code.visualstudio.com/docs/extensionAPI/extension-points#_contributeslanguages