private void CompileLazyList(ElaGenerator s, LabelMap map, Hints hints)
{
var fun = CompileRecursiveFor(s, map, hints, -1, -1);
CompileExpression(s.Target, map, Hints.None, s);
PushVar(fun);
cw.Emit(Op.Call);
}
private void CompileGenerator(ElaGenerator s, LabelMap map, Hints hints)
{
StartScope(false, s.Line, s.Column);
var iter = cw.DefineLabel();
var breakExit = cw.DefineLabel();
var newMap = new LabelMap(map);
var addr = -1;
if (s.Pattern.Type == ElaNodeType.NameReference)
addr = AddVariable(s.Pattern.GetName(), s.Pattern, ElaVariableFlags.None, -1);
else
addr = AddVariable();
var serv = AddVariable();
CompileExpression(s.Target, map, Hints.None, s);
cw.Emit(Op.Dup);
PopVar(serv);
cw.Emit(Op.Isnil);
cw.Emit(Op.Brtrue, breakExit);
cw.MarkLabel(iter);
PushVar(serv);
cw.Emit(Op.Isnil);
cw.Emit(Op.Brtrue, breakExit);
PushVar(serv);
cw.Emit(Op.Head);
PopVar(addr);
PushVar(serv);
cw.Emit(Op.Tail);
PopVar(0 | ((addr >> 8) + 1) << 8);
if (s.Pattern.Type != ElaNodeType.NameReference)
CompilePattern(addr, s.Pattern, iter, false /*allowBang*/, false /*forceStrict*/);
if (s.Guard != null)
{
CompileExpression(s.Guard, map, Hints.None, s);
cw.Emit(Op.Brfalse, iter);
}
if (s.Body != null)
{
CompileExpression(s.Body, newMap, Hints.Scope, s);
if (s.Body.Type != ElaNodeType.Generator)
cw.Emit(Op.Cons);
}
cw.Emit(Op.Br, iter);
cw.MarkLabel(breakExit);
EndScope();
cw.Emit(Op.Nop);
}
private ElaExpression GetSelect(ElaGenerator gen, StringBuilder sb)
{
gen.Pattern.ToString(sb, 0);
sb.Append(" <- ");
gen.Target.ToString(sb, 0);
if (Guard != null)
{
sb.Append(" | ");
gen.Guard.ToString(sb, 0);
}
if (gen.Body.Type == ElaNodeType.Generator)
{
sb.Append(',');
return GetSelect((ElaGenerator)gen.Body, sb);
}
else
return gen.Body;
}
private ElaExpression GetSelect(ElaGenerator gen, StringBuilder sb)
{
gen.Pattern.ToString(sb, 0);
sb.Append(" <- ");
gen.Target.ToString(sb, 0);
if (Guard != null)
{
sb.Append(" | ");
gen.Guard.ToString(sb, 0);
}
if (gen.Body.Type == ElaNodeType.Generator)
{
sb.Append(',');
return(GetSelect((ElaGenerator)gen.Body, sb));
}
else
{
return(gen.Body);
}
}
private int CompileRecursiveFor(ElaGenerator s, LabelMap map, Hints hints, int parent, int parentTail)
{
var funAddr = AddVariable();
StartSection();
StartScope(true, s.Line, s.Column);
cw.StartFrame(1);
var funSkipLabel = cw.DefineLabel();
cw.Emit(Op.Br, funSkipLabel);
var address = cw.Offset;
var exitLab = cw.DefineLabel();
var endLab = cw.DefineLabel();
var iterLab = cw.DefineLabel();
var head = AddVariable();
var tail = AddVariable();
var sys = AddVariable();
cw.Emit(Op.Dup);
PopVar(sys);
cw.Emit(Op.Isnil);
cw.Emit(Op.Brtrue, endLab);
PushVar(sys);
cw.Emit(Op.Head);
PopVar(head);
PushVar(sys);
cw.Emit(Op.Tail);
PopVar(tail);
if (s.Pattern.Type == ElaNodeType.NameReference)
{
var addr = AddVariable(s.Pattern.GetName(), s.Pattern, ElaVariableFlags.None, -1);
PushVar(head);
PopVar(addr);
}
else
CompilePattern(head, s.Pattern, iterLab, false /*allowBang*/, false /*forceStrict*/);
if (s.Guard != null)
{
CompileExpression(s.Guard, map, Hints.None, s);
cw.Emit(Op.Brfalse, iterLab);
}
if (s.Body.Type == ElaNodeType.Generator)
{
var f = (ElaGenerator)s.Body;
var child = CompileRecursiveFor(f, map, hints, funAddr, tail);
CompileExpression(f.Target, map, Hints.None, f);
PushVar(child);
cw.Emit(Op.Call);
cw.Emit(Op.Br, exitLab);//
}
else
{
PushVar(tail);
PushVar(1 | (funAddr >> 8) << 8);
cw.Emit(Op.LazyCall);
CompileExpression(s.Body, map, Hints.None, s);
cw.Emit(Op.Cons);
cw.Emit(Op.Br, exitLab);
}
cw.MarkLabel(iterLab);
PushVar(tail);
PushVar(1 | (funAddr >> 8) << 8);
cw.Emit(Op.Call);
cw.Emit(Op.Br, exitLab);//
cw.MarkLabel(endLab);
if (parent == -1)
cw.Emit(Op.Newlist);
else
{
PushVar(1 | (parentTail >> 8) << 8);
PushVar(2 | (parent >> 8) << 8);
cw.Emit(Op.Call);
}
cw.MarkLabel(exitLab);
cw.Emit(Op.Ret);
frame.Layouts.Add(new MemoryLayout(currentCounter, cw.FinishFrame(), address));
EndSection();
EndScope();
cw.MarkLabel(funSkipLabel);
cw.Emit(Op.PushI4, 1);
cw.Emit(Op.Newfun, frame.Layouts.Count - 1);
PopVar(funAddr);
return funAddr;
}
void ComprehensionEntry(ElaExpression body, out ElaGenerator it)
{
it = new ElaGenerator(t);
it.Body = body;
var cexp = default(ElaExpression);
var pat = default(ElaExpression);
Expr(out pat);
Expect(64);
Expr(out cexp);
it.Pattern = pat;
it.Target = cexp;
if (la.kind == 23 || la.kind == 56) {
if (la.kind == 56) {
var cit = default(ElaGenerator);
Get();
ComprehensionEntry(body, out cit);
it.Body = cit;
} else {
Get();
Expr(out cexp);
it.Guard = cexp;
if (la.kind == 56) {
var cit = default(ElaGenerator);
Get();
ComprehensionEntry(body, out cit);
it.Body = cit;
}
}
}
}
