1274955Ssvnmir//===- iterator_range.h - A range adaptor for iterators ---------*- C++ -*-===// 2274955Ssvnmir// 3353358Sdim// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4353358Sdim// See https://llvm.org/LICENSE.txt for license information. 5353358Sdim// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6274955Ssvnmir// 7274955Ssvnmir//===----------------------------------------------------------------------===// 8274955Ssvnmir/// \file 9274955Ssvnmir/// This provides a very simple, boring adaptor for a begin and end iterator 10274955Ssvnmir/// into a range type. This should be used to build range views that work well 11274955Ssvnmir/// with range based for loops and range based constructors. 12274955Ssvnmir/// 13274955Ssvnmir/// Note that code here follows more standards-based coding conventions as it 14274955Ssvnmir/// is mirroring proposed interfaces for standardization. 15274955Ssvnmir/// 16274955Ssvnmir//===----------------------------------------------------------------------===// 17274955Ssvnmir 18274955Ssvnmir#ifndef LLVM_ADT_ITERATOR_RANGE_H 19274955Ssvnmir#define LLVM_ADT_ITERATOR_RANGE_H 20274955Ssvnmir 21321369Sdim#include <iterator> 22274955Ssvnmir#include <utility> 23274955Ssvnmir 24274955Ssvnmirnamespace llvm { 25274955Ssvnmir 26341825Sdim/// A range adaptor for a pair of iterators. 27274955Ssvnmir/// 28274955Ssvnmir/// This just wraps two iterators into a range-compatible interface. Nothing 29274955Ssvnmir/// fancy at all. 30274955Ssvnmirtemplate <typename IteratorT> 31274955Ssvnmirclass iterator_range { 32274955Ssvnmir IteratorT begin_iterator, end_iterator; 33274955Ssvnmir 34274955Ssvnmirpublic: 35296417Sdim //TODO: Add SFINAE to test that the Container's iterators match the range's 36296417Sdim // iterators. 37296417Sdim template <typename Container> 38296417Sdim iterator_range(Container &&c) 39296417Sdim //TODO: Consider ADL/non-member begin/end calls. 40296417Sdim : begin_iterator(c.begin()), end_iterator(c.end()) {} 41274955Ssvnmir iterator_range(IteratorT begin_iterator, IteratorT end_iterator) 42274955Ssvnmir : begin_iterator(std::move(begin_iterator)), 43274955Ssvnmir end_iterator(std::move(end_iterator)) {} 44274955Ssvnmir 45274955Ssvnmir IteratorT begin() const { return begin_iterator; } 46274955Ssvnmir IteratorT end() const { return end_iterator; } 47360784Sdim bool empty() const { return begin_iterator == end_iterator; } 48274955Ssvnmir}; 49274955Ssvnmir 50341825Sdim/// Convenience function for iterating over sub-ranges. 51274955Ssvnmir/// 52274955Ssvnmir/// This provides a bit of syntactic sugar to make using sub-ranges 53274955Ssvnmir/// in for loops a bit easier. Analogous to std::make_pair(). 54274955Ssvnmirtemplate <class T> iterator_range<T> make_range(T x, T y) { 55274955Ssvnmir return iterator_range<T>(std::move(x), std::move(y)); 56274955Ssvnmir} 57280031Sdim 58280031Sdimtemplate <typename T> iterator_range<T> make_range(std::pair<T, T> p) { 59280031Sdim return iterator_range<T>(std::move(p.first), std::move(p.second)); 60274955Ssvnmir} 61296417Sdim 62280031Sdim} 63274955Ssvnmir 64274955Ssvnmir#endif 65