_Import special form
The following special form converts a C function pointer to SML# function.
exp : _import (ty1, ..., tyn) -> ty where
- exp is a C pointer expression of type unit ptr obtained by DynamicLink.dlsym,
- (ty1, ..., tyn) specifies the types of the arguments. The number and the types must agree with those of C function specification.
- ty is the type of return value.
This is a shorthand for the following more primitive _ffiapply special form:
fn (x1,...,xn) => _ffiapply exp (x1:ty1, ..., xn:tyn) : ty