ifelse — Conditional statement with alternative.
ifelse is obsolete and is only provided for
reasons of backward compatibility.
if should be used instead.
ifelse( : : Condition : )
ifelse is a conditional statement with an alternative.
If the condition is true (i.e., not 0),
all expressions and calls between the head
else are performed.
If the condition is false (i.e., 0)
the part between
endif is executed.
Note that the operator is called
ifelse and it is
if in the program text area.
Condition for the if statement.
Default value: 1
If the condition is correct
ifelse (as operator) returns TRUE. Otherwise, an
exception is raised and an error code returned.