public override IUnboundExpr Transform(AssignExpr expr)
{
// replaces:
//
// a, b <- Foo
//
// with:
//
// def __temp1 <- Foo
// a <- _temp1.0
// b <- _temp1.1
TupleExpr tuple = expr.Target as TupleExpr;
// ignore other assignments
if (tuple == null)
{
return(expr);
}
var exprs = new List <IUnboundExpr>();
var temp = mNameGenerator.Generate();
// evaluate the right-hand side once
exprs.Add(new DefineExpr(expr.Target.Position, temp, expr.Value, false));
// split out the fields
int index = 0;
foreach (var field in tuple.Fields)
{
exprs.Add(new AssignExpr(expr.Position, field, new CallExpr(new IntExpr(index), new NameExpr(expr.Position, temp))));
index++;
}
return(new BlockExpr(false, exprs));
}
IBoundExpr IUnboundExprVisitor<IBoundExpr>.Visit(TupleExpr expr)
{
return new BoundTupleExpr(expr.Fields.Accept(this));
}
public virtual IUnboundExpr Transform(TupleExpr expr)
{
return(expr);
}
IUnboundExpr IUnboundExprVisitor <IUnboundExpr> .Visit(TupleExpr expr)
{
return(Call("TupleExpr", Array(expr.Fields.Accept(this))));
}
