Install:
npm i -D flow-bin
npm i -g flow-bin
Init:
flow init
Script:
"typecheck": "flow src"
Check the src folder.
Add mark to the file which you want to check:
/*@flow */
function to be checked:
function add(x: number, y: number){
return x + y;
}
add(1, '2');
When the flow runs, it will report the error because '2' we passed in is a string not a number.
Notic: Flow only works with Mac and Linux.
See more: Link