cli-watch is a cmd tool to run shell while files changed.
npm i -g cli-watch
watch -f a.js -r 'uglifyjs a.js -o b.js'
This command will watch a.js, and run uglifyjs a.js -o b.js when it changed.
You can use glob patterns for the files param, such as:
watch -f '*.js' -r 'uglifyjs ${p} -o ${n}.min.js'
-h, --help output usage information
-V, --version output the version number
-f, --files [value] glob files pattern, use ; to separate multiple path
-r, --run [value] run command while files changed, you can use ${p} to instead of the changed file path, and use ${n} to instead of the name of changed file path without ext
-n, --dontRunWhileStart dont run the command while start watch