local variable of array act like a global variable

RouterOS Scripting
1
  1. The local variable which type is array, sometime it act like a global variable, for example:
:local testArr {1;2;3}
:log info "step1:testArr[0]=$($testArr->0)"
:set ($testArr->0) 11
:log info "step2:testArr[0]=$($testArr->0)"

when execute it for the first time, the output was:
step1:testArr[0]=1
step2:testArr[0]=11

from the second time, the output was:
step1:testArr[0]=11
step2:testArr[0]=11

So it seems that the local variable of testArr kept the old value and not reinit from the second time.

2.If the array was defined in function and as a return value of this function, then the same array value will be held by multi place. for example:
func1:

:global func1 do={
    :global func3
    :global func2
    :local arr1 [$func3]
    :log info "in func1: before execute func2:$($arr1->0)"
	$func2

    :log info "in func1: after execute func2:$($arr1->0)"
    
}

func2:

:global func2 do={
    :global func3
    :local arr2 [$func3]
    :set ($arr2->0) 20
}

func3:

:global func3 do={
    :local arra {8;4;5}
    :log info "in func3: $($arra->0)"
    return $arra
}

then execute func1 with this code:

:global func1

$func1

and the output was:
in func3: 8
in func1: before execute func2:8
in func3: 8
in func1: after execute func2:20

It means that the variable of arr2 in func2 and arr1 in func1 hold the same array variable, and they will affect each other.

Since i defined the array as local variable, these behaviors was not i want.

But these problems only occur when define the array with constants. for example

:local arr {1;2;3}

or

:local arr ({})

if define the array with:

:local arr {$a1;$b1;$c1}

or

:local arr [:toarry ""]
:set ($arr->0) 1
:set ($arr->1) 2
:set ($arr->2) 3

then it’s no problem.

2

H, that’s very interesting. Never seen a local variable acting like a global. Just makes no sense. Tbh, there are a lot of things that don’t make ANY sense. Literally. N O N E.