How to implement complicated auto-indentation in VScode

Question

I am working on a language extension for SAS for VScode. I previously worked on the SAS language extension for Atom (https://github.com/akanosora/language-sas) as well as Vi

Answer 1

You can add the data and proc keywords themselves to the "decreaseIndentPattern" rule. This way, these keywords will serve for both un-indenting the current line, and starting a new indentation block on the next line.

Consider this, for example:

"indentationRules": {
    "increaseIndentPattern": "^\\s*(proc|data)\\s+.*;\\s*$",
    "decreaseIndentPattern": "^\\s*(run|((proc|data)\\s+.*))\\s*;"
}