internal override void EmitUnset(CodeGenerator codeGenerator)
{
ChainBuilder chain = codeGenerator.ChainBuilder;
// Template: "unset(x[y])" Operators.UnsetItem(object obj,object index)
// Case 3: a_[x]_[x] never reached
Debug.Assert(chain.IsArrayItem == false);
// Case 4,5 never reached
// 4: a[x]->...
// 5: ...->a[]->...
Debug.Assert(chain.IsMember == false);
chain.QuietRead = true;
// 1, 2, 6, 7
if (this.isMemberOf != null)
{
// 6 , 7: ...->a[]_[]_ , ...->a_[]_
chain.Create();
chain.Begin();
chain.Lengthen(); // for hop over ->
isMemberOf.Emit(codeGenerator);
chain.IsArrayItem = true;
chain.IsLastMember = false;
chain.EmitUnsetItem(array, index);
chain.IsArrayItem = false;
chain.End();
return;
}
// 1, 2
if (array is ItemUse || array is DirectStFldUse || array is IndirectStFldUse /* ??? */)
{
// 2: a[]_[]_
chain.Create();
chain.Begin();
chain.IsArrayItem = true;
chain.IsLastMember = true;
chain.EmitUnsetItem(array, index);
chain.IsArrayItem = false;
chain.End();
return;
}
// 1: a_[x]_
chain.IsArrayItem = true;
chain.IsLastMember = true;
chain.EmitUnsetItem(array, index);
chain.IsArrayItem = false;
}