Renaming functions locally inside other functions

Question

Have written a function named linge. How can I use a replacement for the function name inside another function, locally using a different name such as lg?

2

Why do you need to do this? – Barmar Sep 08 '21 at 21:49

Barmar · Answer 1 · 2021-09-08T22:12:17.543

0

Simply define lg to call ligne.

function otherFunc() {
    function lg() { ligne "$@"; }
    lg 1 2 3
}

Note that this will define a global function lg, too. See Achieve Local Function for how to work around this by defining the function to run in a subshell.

function otherFunc() (
    function lg() { ligne "$@"; }
    lg 1 2 3
)

But if you do this, any variable assignments done in the function will also not be visible outside the function.

edited Sep 08 '21 at 22:12

answered Sep 08 '21 at 21:53

Barmar

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Have studied the link where the function is defined in a subshell. Can I use a subshell within a normal function using `{...}`? – Angio Sep 08 '21 at 22:05
Subshells require `(...)` – Barmar Sep 08 '21 at 22:08
I meant to say, a subshell with `(...)` within a normal function defined using `{...}`. – Angio Sep 08 '21 at 22:24
Of course. You can use that inside the function just like you can anywhere else. – Barmar Sep 08 '21 at 22:29
I have put a solution up. – Angio Sep 08 '21 at 22:36
I am quite unsure about writing a function that can evaluate itself to `0` or `1`. Does one use `return 0` and `return 0` at the end or does one use `echo "0"` and `echo "1"` instead? – Angio Sep 08 '21 at 22:53
@Angio `return` sets the exit status of the function, which you can check in the caller using `if` or `$?`. `echo` writes output, which you can capture using `$(command)`. It depends on what the purpose of the function is. – Barmar Sep 09 '21 at 14:10
Understood. Thank you. – Angio Sep 09 '21 at 14:25
Why do you include "$@" as arguments to 'lg' in the declaration `function lg() { ligne "$@"; }`. Are the parameters "$@" taken from the parameters coming through `otherFunc`? – Angio Sep 09 '21 at 14:36
Yes, of course. How else would `lg` get the parameters? – Barmar Sep 09 '21 at 14:37
My assumption has been that "$@" in `lg` are tho parameter arguments for `lg`, rather than the parameter arguments set by `otherFunc`. The parameters to `otherFunc` could very well be different than the parameters to `lg`. – Angio Sep 09 '21 at 15:51
Inside `lg`, `$@` is the arguments to `lg`, not `otherFunc`. – Barmar Sep 09 '21 at 15:53
Every function has its own set of `$1, $2, $3, $@` – Barmar Sep 09 '21 at 15:53
Good. I follow and it is as it should be. Thank you. – Angio Sep 09 '21 at 15:55

Angio · Answer 2 · 2021-09-09T16:00:13.420

Have had a go using a subshell inside the function

myfunc ()
{
 val="Fred" 
 (
  function lg() { linge "$@"; }

  lg "$src" && printf '%s\n' "No src used"
  lg "$dst" && printf '%s\n' "No dst used"
  val="Joe"
 )
 echo "val: $val"
 echo "More commands follow"

}

Running the function myfunc gives

val: Fred

The above means that val="Joe" is local to the sub-shell. Would it be possible to got some variable inside the sub-shell that can be transferred outside the sub-shell (which will be used as a flag) for use by myfunc.

Renaming functions locally inside other functions

2 Answers2