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What is the use case for noEmit in Typescript? I'm interested because I want to see if I can use this for development where I'll compile and run the compiled code without outputting them onto the file system which would be more efficient.

Edit: Perhaps this would be straight forward: "Can I use noEmit tag in typescript to compile and run the code without outputting them onto the file system? If so, how would I do that?"

hwkd
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  • @H.B. I'm pretty sure there is a "real correct answer". I narrowed it down to whether I can use it for compiling and running without emitting output. – hwkd Mar 05 '19 at 12:37
  • Your question is a bit misleading then, because the very first sentence appears to ask about the flag in general. – H.B. Mar 05 '19 at 13:44
  • I've updated the question. – hwkd Mar 06 '19 at 01:29

2 Answers2

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It's used when tsc is used only for type checking, not for compilation. That's the case when some other tool (like Webpack, Parcel or Rollup) is responsible for compiling your code.

If you are interested in running your code in an interactive mode, look into ts-node or ts-node-dev.

johannchopin
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Karol Majewski
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"The noEmit option tells TypeScript that we only want to run type checking and do not want the compiler to output any transpiled code".

Such as pipelines where you just want to see if there is a typing error before merging with main branch.

Coşkun Uyar
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