switch(EXPR, ...)
EXPR
| an expression that evaluates to a number or a character string |
...
| the list of alternatives, given explicitly |
switch
evaluates EXPR
if the value is an integer between
1 and nargs()-1
then the corresponding element of ...
is
evaluated and the result returned.
If EXPR
returns a character string then that string is used to
match the names of the elements in ...
. If there is an exact match
then that element is evaluated and the result returned.