Struct Constructors

Sometimes, you want to define extra constructors for a struct, you can do this with a ctor function.

struct Point {
  x: int;
  y: int;
ctor Point (a:int) => Point (a,a);
var p = Point 42;

In fact, this works for any type, not just a struct, provided the type has a single word name. If it doesn’t, you can always introduce a typedef:

typedef pair = int * int;
ctor pair (x:int) => x,x;

Using a typedef is a way to introduce an extra constructor for a type with the same signature; that is, provide named constructors. For example:

struct complex {
  x: double;
  y: double;

typedef polar = complex;
ctor polar (modulus: double, argument: double) =>
  complex (modulus * cos argument, modulus * sin argument)