Typescript Useful Compilation Options

If you’re using typescript (tsc) to compile your typescript files, there are some handy compilation options that can give you more insight into how compilation happens or why certain files are compiled.

Using the tsconfig.json you can change what the output directory or location of the built javascript is. Sometimes if you’re changing that location it can be tedious to go back and delete all the files that were built. Use the --build flag along with the --clean flags to delete all the built javascript files.

# delete all built javascript files
tsc --build --clean

Want to see the typescript files that are being built from in your codebase? Use the --listFiles to build and also output a list of the files that were used to build your javascript.

# list all the source typescript files being used to build your javascript
tsc --listFiles

With the tsconfig.json compilerOptions module setting you can set how the compiler decides to what to import. You can see the log output of this process by using the --traceResolution flag. This verbose output can be useful if there is a problem with some files being compiled that you don’t want or if you want to decide which module pattern you want to use in your compilerOptions.

# see output of the module resolution from typescript
npx tsc --traceResolution