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TS6133 Error if using typescript with noUnusedLocals and typescript preprocessor

See original GitHub issue

The functions declared in the output parser cause TS6133 errors when attempting to compile with typescript. This is because understandably, not all functions that are provided by builtins and generators are used in a user’s grammar.

How to reproduce:

grammar.ne

@preprocessor typescript
@builtin "postprocessors.ne"

main -> foo
foo -> "foo"i
bash-3.2$ tsc -v
Version 2.6.1

bash-3.2$ nearleyc -v
2.11.0

bash-3.2$ nearleyc grammar.ne -o parser.ts

bash-3.2$ tsc --noUnusedLocals
parser.ts: error TS6133: 'id' is declared but never used.
parser.ts: error TS6133: 'nth' is declared but never used.
parser.ts: error TS6133: '$' is declared but never used.

Issue Analytics

  • State:closed
  • Created 6 years ago
  • Comments:11

github_iconTop GitHub Comments

1reaction
glmdgrielsoncommented, Nov 28, 2017

The official website says:

A // @ts-ignore comment suppresses all errors that originate on the following line.

So… I’m not so sure. But if it works for you, then I guess that works!
On that note, that solves my problem handily.

1reaction
tjvrcommented, Nov 28, 2017

// @ts-ignore seems fine to me. My worry is, will this hide other TS issues? Will think disable type-checking for that line, and is there any way that might cause problems?

Happy to merge if not 👍

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