| //===- llvm/ADT/STLExtras.h - Useful STL related functions ------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file was developed by the LLVM research group and is distributed under |
| // the University of Illinois Open Source License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file contains some templates that are useful if you are working with the |
| // STL at all. |
| // |
| // No library is required when using these functinons. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_ADT_STLEXTRAS_H |
| #define LLVM_ADT_STLEXTRAS_H |
| |
| #include <functional> |
| #include <utility> // for std::pair |
| #include <cstring> // for std::size_t |
| #include "llvm/ADT/iterator" |
| |
| namespace llvm { |
| |
| //===----------------------------------------------------------------------===// |
| // Extra additions to <functional> |
| //===----------------------------------------------------------------------===// |
| |
| template<class Ty> |
| struct greater_ptr : public std::binary_function<Ty, Ty, bool> { |
| bool operator()(const Ty* left, const Ty* right) const { |
| return *right < *left; |
| } |
| }; |
| |
| // deleter - Very very very simple method that is used to invoke operator |
| // delete on something. It is used like this: |
| // |
| // for_each(V.begin(), B.end(), deleter<Interval>); |
| // |
| template <class T> |
| static inline void deleter(T *Ptr) { |
| delete Ptr; |
| } |
| |
| |
| |
| //===----------------------------------------------------------------------===// |
| // Extra additions to <iterator> |
| //===----------------------------------------------------------------------===// |
| |
| // mapped_iterator - This is a simple iterator adapter that causes a function to |
| // be dereferenced whenever operator* is invoked on the iterator. |
| // |
| template <class RootIt, class UnaryFunc> |
| class mapped_iterator { |
| RootIt current; |
| UnaryFunc Fn; |
| public: |
| typedef typename std::iterator_traits<RootIt>::iterator_category |
| iterator_category; |
| typedef typename std::iterator_traits<RootIt>::difference_type |
| difference_type; |
| typedef typename UnaryFunc::result_type value_type; |
| |
| typedef void pointer; |
| //typedef typename UnaryFunc::result_type *pointer; |
| typedef void reference; // Can't modify value returned by fn |
| |
| typedef RootIt iterator_type; |
| typedef mapped_iterator<RootIt, UnaryFunc> _Self; |
| |
| inline const RootIt &getCurrent() const { return current; } |
| |
| inline explicit mapped_iterator(const RootIt &I, UnaryFunc F) |
| : current(I), Fn(F) {} |
| inline mapped_iterator(const mapped_iterator &It) |
| : current(It.current), Fn(It.Fn) {} |
| |
| inline value_type operator*() const { // All this work to do this |
| return Fn(*current); // little change |
| } |
| |
| _Self& operator++() { ++current; return *this; } |
| _Self& operator--() { --current; return *this; } |
| _Self operator++(int) { _Self __tmp = *this; ++current; return __tmp; } |
| _Self operator--(int) { _Self __tmp = *this; --current; return __tmp; } |
| _Self operator+ (difference_type n) const { return _Self(current + n); } |
| _Self& operator+= (difference_type n) { current += n; return *this; } |
| _Self operator- (difference_type n) const { return _Self(current - n); } |
| _Self& operator-= (difference_type n) { current -= n; return *this; } |
| reference operator[](difference_type n) const { return *(*this + n); } |
| |
| inline bool operator!=(const _Self &X) const { return !operator==(X); } |
| inline bool operator==(const _Self &X) const { return current == X.current; } |
| inline bool operator< (const _Self &X) const { return current < X.current; } |
| |
| inline difference_type operator-(const _Self &X) const { |
| return current - X.current; |
| } |
| }; |
| |
| template <class _Iterator, class Func> |
| inline mapped_iterator<_Iterator, Func> |
| operator+(typename mapped_iterator<_Iterator, Func>::difference_type N, |
| const mapped_iterator<_Iterator, Func>& X) { |
| return mapped_iterator<_Iterator, Func>(X.getCurrent() - N); |
| } |
| |
| |
| // map_iterator - Provide a convenient way to create mapped_iterators, just like |
| // make_pair is useful for creating pairs... |
| // |
| template <class ItTy, class FuncTy> |
| inline mapped_iterator<ItTy, FuncTy> map_iterator(const ItTy &I, FuncTy F) { |
| return mapped_iterator<ItTy, FuncTy>(I, F); |
| } |
| |
| |
| // next/prior - These functions unlike std::advance do not modify the |
| // passed iterator but return a copy. |
| // |
| // next(myIt) returns copy of myIt incremented once |
| // next(myIt, n) returns copy of myIt incremented n times |
| // prior(myIt) returns copy of myIt decremented once |
| // prior(myIt, n) returns copy of myIt decremented n times |
| |
| template <typename ItTy, typename Dist> |
| inline ItTy next(ItTy it, Dist n) |
| { |
| std::advance(it, n); |
| return it; |
| } |
| |
| template <typename ItTy> |
| inline ItTy next(ItTy it) |
| { |
| std::advance(it, 1); |
| return it; |
| } |
| |
| template <typename ItTy, typename Dist> |
| inline ItTy prior(ItTy it, Dist n) |
| { |
| std::advance(it, -n); |
| return it; |
| } |
| |
| template <typename ItTy> |
| inline ItTy prior(ItTy it) |
| { |
| std::advance(it, -1); |
| return it; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Extra additions to <utility> |
| //===----------------------------------------------------------------------===// |
| |
| // tie - this function ties two objects and returns a temporary object |
| // that is assignable from a std::pair. This can be used to make code |
| // more readable when using values returned from functions bundled in |
| // a std::pair. Since an example is worth 1000 words: |
| // |
| // typedef std::map<int, int> Int2IntMap; |
| // |
| // Int2IntMap myMap; |
| // Int2IntMap::iterator where; |
| // bool inserted; |
| // tie(where, inserted) = myMap.insert(std::make_pair(123,456)); |
| // |
| // if (inserted) |
| // // do stuff |
| // else |
| // // do other stuff |
| |
| namespace |
| { |
| template <typename T1, typename T2> |
| struct tier { |
| typedef T1 &first_type; |
| typedef T2 &second_type; |
| |
| first_type first; |
| second_type second; |
| |
| tier(first_type f, second_type s) : first(f), second(s) { } |
| tier& operator=(const std::pair<T1, T2>& p) { |
| first = p.first; |
| second = p.second; |
| return *this; |
| } |
| }; |
| } |
| |
| template <typename T1, typename T2> |
| inline tier<T1, T2> tie(T1& f, T2& s) { |
| return tier<T1, T2>(f, s); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Extra additions to arrays |
| //===----------------------------------------------------------------------===// |
| |
| /// Find where an array ends (for ending iterators) |
| /// This returns a pointer to the byte immediately |
| /// after the end of an array. |
| template<class T, std::size_t N> |
| inline T *array_endof(T (&x)[N]) { |
| return x+N; |
| } |
| |
| /// Find the length of an array. |
| template<class T, std::size_t N> |
| inline size_t array_lengthof(T (&x)[N]) { |
| return N; |
| } |
| |
| } // End llvm namespace |
| |
| #endif |