x =
mustBeA (x, type)
¶x =
mustBeA (x, type, label)
¶Requires that input is of a given type.
Raises an error if the input x is not of type type, as determined by
isa (x, type)
.
label is an optional input that determines how the input will be described in
error messages. If not supplied, inputname (1)
is used, and if that is
empty, it falls back to "input".