Re: Passing variables by reference conflicts with local

[Matthew Woehlke]

Freddy Vulto wrote:
>      # Param: $1 �variable name to return value to
>      # Public library function
>      blackbox() {
>          local __1
>          _blackbox __1
>          [[ $1 == __1 ]]&&  echo "ERROR: variable name conflicts"\
>                  "with local variable: $1"
>          printf -v $1 %s "$__1"
>      }


  # Param: $1 �variable name to return value to
  # Public library function
  blackbox() {
    [[ "$1" =~ [_[:alpha:]][_[:alnum:]]* ]] || die # TODO: error instead
    if [ $1 == "__1" ]; then
      local __2
      _blackbox __2
      printf -v $1 %s "$__2"
    else
      local __1
      _blackbox __1
      printf -v $1 %s "$__1"
    fi
  }

Wouldn't that avoid having variable names that can't be used?



It should be possible to place this code in a generic wrapper such that 
you can do:

blackbox1() { call_varref _blackbox1 "$@"; }
blackbox2() { call_varref _blackbox2 "$@"; }

This requires, of course, that only one variable is 'passed by-ref' and 
is at a consistent position (though you could easily add a parameter 
specifying what position). How to do this is left as an exercise for the 
reader :-).

--
Matthew
Please do not quote my e-mail address unobfuscated in message bodies.
--
Oops. -- Shannon Foraker (David Weber, Ashes of Victory)