These are the 2 ways to generate type declaration files in TypeScript:
- Pass the
--declarationflag while executing the
- Set the
Generate Type Declaration Files Using Compiler Flag
When working with TypeScript, you can use the compiler flag
--declaration with the
tsc command to automatically generate declaration files.
Generate declaration files for the entire project:
This command will compile all of your TypeScript files and generate type declaration files for them.
Generate a declaration file for a single TypeScript file:
tsc --declaration main.ts
This command will only compile the
main.ts file and generate the
main.d.ts declaration file.
Set Configuration Option in tsconfig.json File
If you don't want to use the
--declaration flag every time you run the
tsc command, you can set the configuration option
"declaration": true in your
When you set this option and run
tsc command, the TypeScript compiler will compile all the TypeScript files and generate type declaration files for them automatically.
Every time you don't have to use any compiler flag.
But if you try to compile a single file with this option, it won't generate the declaration file for that. You have to use the
--declaration flag if you run the
tsc command with a filename.
When you run the
tsc command with a filename, it will only compile the TypeScript. You won't get the
main.d.ts file. This option only works for the
That's how you can generate type declaration files automatically using the TypeScript compiler. I have shown you 2 ways in this blog post.
If you compile your TypeScript files frequently then setting the declaration option in your tsconfig.json file is a good choice. This way you don't have to type the
--declaration flag every time.
But if you don't need to compile your TypeScript files frequently or you want to generate a type declaration file for a single TypeScript file then you can use the