Re: Passing variables by reference conflicts with local

[Freddy Vulto]

It appears that `unset' is capable of traversing down the call-stack and
unsetting variables repeatedly:

    a=0 b=0 c=0 d=0 e=0
    _unset() { unset -v b c c d d d e; }
    t1() {
        local a=1 b=1 c=1 d=1
        t2
    }
    t2() {
        local a=2 b=2 c=2 d=2 e=2
        _unset
        echo a:$a b:$b c:$c d:$d e:$e
    }
    t1  # Outputs: a:2 b:1 c:0 d: e:0
        #            ^   ^   ^   ^  ^-- unset once (skipped t1)
        #            |   |   |   +----- unset thrice to global
        #            |   |   +--------- unset twice till global
        #            |   +------------- unset once till t1
        #            +----------------- unset not

It seems to work on bash-3.0, 3.2, 4.0 and 4.1.
Is this a bug or a feature?

Freddy Vulto
http://fvue.nl/wiki/Bash:_passing_variables_by_reference