ShaderTools.Hlsl.Parser.DirectiveStack.CompleteIf C# (CSharp) Method

        private static ConsList<Directive> CompleteIf(ConsList<Directive> stack, out bool include)
        {
            // if we get to the top, the default rule is to include anything that follows
            if (!stack.Any())
            {
                include = true;
                return stack;
            }

            // if we reach the #if directive, then we stop unwinding and start
            // rebuilding the stack w/o the #if/#elif/#else/#endif directives
            // only including content from sections that are considered included
            if (stack.Head.Kind.IsIfLikeDirective())
            {
                include = stack.Head.BranchTaken;
                return stack.Tail;
            }

            var newStack = CompleteIf(stack.Tail, out include);
            switch (stack.Head.Kind)
            {
                case SyntaxKind.ElifDirectiveTrivia:
                case SyntaxKind.ElseDirectiveTrivia:
                    include = stack.Head.BranchTaken;
                    break;
                default:
                    if (include)
                    {
                        newStack = new ConsList<Directive>(stack.Head, newStack);
                    }

                    break;
            }

            return newStack;
        }