Forward function declarations in a Bash or a Shell script?

bash, forward-declaration, function, sh

Solution

Great question. I use a pattern like this for most of my scripts:

#!/bin/bash

main() {
    foo
    bar
    baz
}

foo() {
}

bar() {
}

baz() {
}

main "$@"

You can read the code from top to bottom, but it doesn't actually start executing until the last line. By passing `"$@"` to main() you can access the command-line arguments `$1`, `$2`, et al just as you normally would.

Problem

Is there such a thing in `bash` or at least something similar (work-around) like forward declarations, well known in C / C++, for instance? Or there is so such thing because for example it is always executed in one pass (line after line)? If there are no forward declarations, what should I do to make my script easier to read. It is rather long and these function definitions at the beginning, mixed with global variables, make my script look ugly and hard to read / understand)? I am asking to learn some well-known / best practices for such cases. For example: ``` # something like forward declaration function func # execution of the function func # definition of func function func { echo 123 } ```

Original source

Related problems