gistfile1.txt

Macintosh-3: $ cat input.sl 
surface
matte(float Ka = 1.0; float Kd = 1.1;)
{
	normal Nf = faceforward(normalize(N), I);
	Oi = Os;
	Ci = Os * Cs * (Ka * ambient() + Kd * diffuse(Nf));
	

}
Macintosh-3: $ ./lslc input.sl 
// [AST] = [ShaderFunc Surface "matte" [FormalDecl TyFloat "Ka" (Just (F 1.0)),FormalDecl TyFloat "Kd" (Just (F 1.1))] [Def TyNormal "Nf" (Just (Call TyUndef "faceforward" [Call TyUndef "normalize" [Var TyUndef "N"],Var TyUndef "I"])),Assign TyUndef (Var TyUndef "Oi") (Var TyUndef "Os"),Assign TyUndef (Var TyUndef "Ci") (BinOp TyUndef OpMul [BinOp TyUndef OpMul [Var TyUndef "Os",Var TyUndef "Cs"],BinOp TyUndef OpAdd [BinOp TyUndef OpMul [Var TyUndef "Ka",Call TyUndef "ambient" []],BinOp TyUndef OpMul [Var TyUndef "Kd",Call TyUndef "diffuse" [Var TyUndef "Nf"]]]])]]
surface matte(float Ka, float Kd) {
    normal Nf = faceforward(normalize(N), I);
    Oi = Os;
    Ci = ( ( Os * Cs ) * ( ( Ka * ambient() ) + ( Kd * diffuse(Nf) ) ) );

}