How to capitalize the first letter?

[fovj]

upper and lower is fine.

But I don't know if there is a corresponding way to capitalize the first letter.

  s(
    "us",
    fmt("const [{}, set{setter}] = useState({})", {
      i(1, "value"),
      i(2, "initialValue"),
      setter = l(l._1:upper(), 1)
    })
  ),

[L3MON4D3]

Just a bit of playing around with string-functions:
setter = l(l._1:sub(1,1):upper() .. l._1:sub(2,-1)))
(so extract first char, capitalize, append remaining chars)

[marcoSven]

I am using my vscode snippets. Is there an existing solution to get TextMate variable transformation working?

"useState": {
  "prefix": "useState",
  "body": [
    "const [${2:state}, set${2/(.*)/${1:/capitalize}/}] = useState$1(${3:initialState})"
  ]
},

[marcoSven]

I figured it out or at least I resolved it. The issue was related to "jsregexp" I think.

build = "make install_jsregexp", or running it manually, didn't result in any errors.
I decided to remove and reinstall all my related plugins and now it works 🤷

[json-bateman]

In case someone stumbles upon this thread again, in the accepted answer it's missing the second argument in the lambda function, the code that works for me:

ls.s(
      "useS",
      fmt("const [{}, set{setter}] = useState({})", {
         i(1, "state"),
         i(2, "initialValue"),
         setter = l(l._1:sub(1, 1):upper() .. l._1:sub(2, -1), 1)
      })
   ),