Name: Anonymous 2012-04-09 16:27
Hey /prog/, can your toy language do this?
MODE P = PROC (P) P;
P i = (P x) P : x;
P v = (P x) P : v;
P k = (P x) P : ((P x, y) P: x)(x, );
P s = (P x) P : ((P x, y) P: ((P x, y, z) P: x(z)(y(z)))(x, y, ))(x, );
P succ = s(s(k(s))(k));
PROC side effect = (PROC VOID f) P : ((PROC VOID f, P x) P : (f; x))(f, );
PROC church = (INT n) P : (P f := k(i); TO n DO f := s(s(k(s))(k))(f) OD; f);
PROC int = (P f) INT : (INT n := 0; f((P x) P : (n +:= 1; i))(i); n);
OP + = (P x, y) P : ((P x, y, z) P : ((P x, y, z, w) P : x(z)(y(z)(w)))(x, y, z, ))(x, y, );
succ(church(10))(side effect(VOID : print(("Hello, world!", new line))))(i);
print(int(succ(church(100) + church(20))))