1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
|
//===- 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 <utility>
inline namespace __swift { inline namespace __runtime {
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 <typename IteratorT>
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 <typename Container>
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 <class T> iterator_range<T> make_range(T x, T y) {
return iterator_range<T>(std::move(x), std::move(y));
}
template <typename T> iterator_range<T> make_range(std::pair<T, T> p) {
return iterator_range<T>(std::move(p.first), std::move(p.second));
}
}
}} // namespace swift::runtime
#endif
|