else keyword in if-then-else and select-case-then-else

## Description

Used with `if` and `select`.

## Examples

    val = %t

    if val==%t then
        disp("true");
    else
        disp("false");
    end

    select val
       case %t then
          disp("true");
       case %f then
          disp("false");
       else
          disp("a third variant");
    end

## See also

- elseif
- if
- select
- &, &&
- |, ||

## History

6.0.0 `else` is now protected: Assignments like `else=1` are no longer possible.