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Golang Defer implement in Javascript

The behavior of defer statements is straightforward and predictable. There are three simple rules:

1. A deferred function’s arguments are evaluated when the defer statement is evaluated.
   √, although you must manually pass arguments.
2. Deferred function calls are executed in Last In First Out order after the surrounding function returns.
   √, just reverse the stack!
3. Deferred functions may read and assign to the returning function’s named return values.
   √, no if return a value, yes return an object. Support async function.

godefer(defer=>{
	...somecode
	defer(somefunc)
	...somecode
	return 42 //return an object for named return values
})

see more usage in test.js

1. Variables declared by let/const can't be use in finally block, have to use var.
2. Deferred functions will not run if encounter errors before, but finally block don't know.