Why does babel convert "true" to "!0"

Question

I have inspected my converted code and i have seen that true is converted to !0

Example:

 let obj = {
    loading: true
 }

Is converted to:

 let obj = {
    loading: !0
 }

Why is that? Is it because of performance reason or because something else?

Answer 1

For minifaction, ie: smaller bundle size. See also: babel-plugin-transform-minify-booleans