Method eval_string_concat

Tools/EditorFramework/pugixml.cpp:9069–9119

	}

	xpath_string eval_string_concat(const xpath_context& c, const xpath_stack& stack)
	{
		assert(_type == ast_func_concat);

		xpath_allocator_capture ct(stack.temp);

		// count the string number
		size_t count = 1;
		for (xpath_ast_node* nc = _right; nc; nc = nc->_next)
			count++;

		// gather all strings
		xpath_string static_buffer[4];
		xpath_string* buffer = static_buffer;

		// allocate on-heap for large concats
		if (count > sizeof(static_buffer) / sizeof(static_buffer[0]))
		{
			buffer = static_cast<xpath_string*>(stack.temp->allocate(count * sizeof(xpath_string)));
			assert(buffer);
		}

		// evaluate all strings to temporary stack
		xpath_stack swapped_stack = {stack.temp, stack.result};

		buffer[0] = _left->eval_string(c, swapped_stack);

		size_t pos = 1;
		for (xpath_ast_node* n = _right; n; n = n->_next, ++pos)
			buffer[pos] = n->eval_string(c, swapped_stack);
		assert(pos == count);

		// get total length
		size_t length = 0;
		for (size_t i = 0; i < count; ++i)
			length += buffer[i].length();

		// create final string
		char_t* result = static_cast<char_t*>(stack.result->allocate((length + 1) * sizeof(char_t)));
		assert(result);

		char_t* ri = result;

		for (size_t j = 0; j < count; ++j)
			for (const char_t* bi = buffer[j].c_str(); *bi; ++bi)
				*ri++ = *bi;

		*ri = 0;

		return xpath_string(result, true);
	}

	xpath_string eval_string(const xpath_context& c, const xpath_stack& stack)
	{