//===- iterator_range.h - A range adaptor for iterators ---------*- C++ -*-===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// /// \file /// This provides a very simple, boring adaptor for a begin and end iterator /// into a range type. This should be used to build range views that work well /// with range based for loops and range based constructors. /// /// Note that code here follows more standards-based coding conventions as it /// is mirroring proposed interfaces for standardization. /// //===----------------------------------------------------------------------===// #ifndef LLVM_ADT_ITERATOR_RANGE_H #define LLVM_ADT_ITERATOR_RANGE_H #include namespace llvm { /// A range adaptor for a pair of iterators. /// /// This just wraps two iterators into a range-compatible interface. Nothing /// fancy at all. template class iterator_range { IteratorT begin_iterator, end_iterator; public: //TODO: Add SFINAE to test that the Container's iterators match the range's // iterators. template iterator_range(Container &&c) //TODO: Consider ADL/non-member begin/end calls. : begin_iterator(c.begin()), end_iterator(c.end()) {} iterator_range(IteratorT begin_iterator, IteratorT end_iterator) : begin_iterator(std::move(begin_iterator)), end_iterator(std::move(end_iterator)) {} IteratorT begin() const { return begin_iterator; } IteratorT end() const { return end_iterator; } bool empty() const { return begin_iterator == end_iterator; } }; /// Convenience function for iterating over sub-ranges. /// /// This provides a bit of syntactic sugar to make using sub-ranges /// in for loops a bit easier. Analogous to std::make_pair(). template iterator_range make_range(T x, T y) { return iterator_range(std::move(x), std::move(y)); } template iterator_range make_range(std::pair p) { return iterator_range(std::move(p.first), std::move(p.second)); } } #endif