Chris Lattner | 4848689 | 2003-09-30 18:37:50 +0000 | [diff] [blame] | 1 | //===- STLExtras.h - Useful functions when working with the STL -*- C++ -*-===// |
John Criswell | b2109ce | 2003-10-20 19:46:57 +0000 | [diff] [blame] | 2 | // |
| 3 | // The LLVM Compiler Infrastructure |
| 4 | // |
| 5 | // This file was developed by the LLVM research group and is distributed under |
| 6 | // the University of Illinois Open Source License. See LICENSE.TXT for details. |
| 7 | // |
| 8 | //===----------------------------------------------------------------------===// |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 9 | // |
| 10 | // This file contains some templates that are useful if you are working with the |
| 11 | // STL at all. |
| 12 | // |
| 13 | // No library is required when using these functinons. |
| 14 | // |
| 15 | //===----------------------------------------------------------------------===// |
| 16 | |
Brian Gaeke | a9f6e4a | 2003-06-17 00:35:55 +0000 | [diff] [blame] | 17 | #ifndef SUPPORT_STLEXTRAS_H |
| 18 | #define SUPPORT_STLEXTRAS_H |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 19 | |
| 20 | #include <functional> |
Brian Gaeke | 9bb2188 | 2003-11-23 03:50:31 +0000 | [diff] [blame] | 21 | #include <utility> // for std::pair |
Chris Lattner | df6f583 | 2002-10-27 19:16:27 +0000 | [diff] [blame] | 22 | #include "Support/iterator" |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 23 | |
Brian Gaeke | d0fde30 | 2003-11-11 22:41:34 +0000 | [diff] [blame] | 24 | namespace llvm { |
| 25 | |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 26 | //===----------------------------------------------------------------------===// |
Chris Lattner | 42e018c | 2001-06-27 23:32:12 +0000 | [diff] [blame] | 27 | // Extra additions to <functional> |
| 28 | //===----------------------------------------------------------------------===// |
| 29 | |
| 30 | // bind_obj - Often times you want to apply the member function of an object |
| 31 | // as a unary functor. This macro is shorthand that makes it happen less |
| 32 | // verbosely. |
| 33 | // |
| 34 | // Example: |
| 35 | // struct Summer { void accumulate(int x); } |
| 36 | // vector<int> Numbers; |
| 37 | // Summer MyS; |
| 38 | // for_each(Numbers.begin(), Numbers.end(), |
| 39 | // bind_obj(&MyS, &Summer::accumulate)); |
| 40 | // |
| 41 | // TODO: When I get lots of extra time, convert this from an evil macro |
| 42 | // |
| 43 | #define bind_obj(OBJ, METHOD) std::bind1st(std::mem_fun(METHOD), OBJ) |
| 44 | |
| 45 | |
| 46 | // bitwise_or - This is a simple functor that applys operator| on its two |
| 47 | // arguments to get a boolean result. |
| 48 | // |
| 49 | template<class Ty> |
Chris Lattner | 697954c | 2002-01-20 22:54:45 +0000 | [diff] [blame] | 50 | struct bitwise_or : public std::binary_function<Ty, Ty, bool> { |
Chris Lattner | 42e018c | 2001-06-27 23:32:12 +0000 | [diff] [blame] | 51 | bool operator()(const Ty& left, const Ty& right) const { |
| 52 | return left | right; |
| 53 | } |
| 54 | }; |
| 55 | |
| 56 | |
Chris Lattner | 577b15f | 2001-07-02 01:09:41 +0000 | [diff] [blame] | 57 | // deleter - Very very very simple method that is used to invoke operator |
| 58 | // delete on something. It is used like this: |
| 59 | // |
Chris Lattner | 8765096 | 2002-04-28 16:18:32 +0000 | [diff] [blame] | 60 | // for_each(V.begin(), B.end(), deleter<Interval>); |
Chris Lattner | 577b15f | 2001-07-02 01:09:41 +0000 | [diff] [blame] | 61 | // |
| 62 | template <class T> |
| 63 | static inline void deleter(T *Ptr) { |
| 64 | delete Ptr; |
| 65 | } |
| 66 | |
| 67 | |
| 68 | |
Chris Lattner | 42e018c | 2001-06-27 23:32:12 +0000 | [diff] [blame] | 69 | //===----------------------------------------------------------------------===// |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 70 | // Extra additions to <iterator> |
| 71 | //===----------------------------------------------------------------------===// |
| 72 | |
| 73 | // mapped_iterator - This is a simple iterator adapter that causes a function to |
| 74 | // be dereferenced whenever operator* is invoked on the iterator. |
| 75 | // |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 76 | template <class RootIt, class UnaryFunc> |
| 77 | class mapped_iterator { |
| 78 | RootIt current; |
Chris Lattner | 643afb3 | 2001-09-07 16:30:28 +0000 | [diff] [blame] | 79 | UnaryFunc Fn; |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 80 | public: |
Chris Lattner | 697954c | 2002-01-20 22:54:45 +0000 | [diff] [blame] | 81 | typedef typename std::iterator_traits<RootIt>::iterator_category |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 82 | iterator_category; |
Chris Lattner | 697954c | 2002-01-20 22:54:45 +0000 | [diff] [blame] | 83 | typedef typename std::iterator_traits<RootIt>::difference_type |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 84 | difference_type; |
| 85 | typedef typename UnaryFunc::result_type value_type; |
Chris Lattner | d063725 | 2002-10-13 19:30:44 +0000 | [diff] [blame] | 86 | |
| 87 | typedef void pointer; |
| 88 | //typedef typename UnaryFunc::result_type *pointer; |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 89 | typedef void reference; // Can't modify value returned by fn |
| 90 | |
| 91 | typedef RootIt iterator_type; |
| 92 | typedef mapped_iterator<RootIt, UnaryFunc> _Self; |
| 93 | |
| 94 | inline RootIt &getCurrent() const { return current; } |
| 95 | |
Chris Lattner | 643afb3 | 2001-09-07 16:30:28 +0000 | [diff] [blame] | 96 | inline explicit mapped_iterator(const RootIt &I, UnaryFunc F) |
| 97 | : current(I), Fn(F) {} |
| 98 | inline mapped_iterator(const mapped_iterator &It) |
| 99 | : current(It.current), Fn(It.Fn) {} |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 100 | |
| 101 | inline value_type operator*() const { // All this work to do this |
Chris Lattner | 643afb3 | 2001-09-07 16:30:28 +0000 | [diff] [blame] | 102 | return Fn(*current); // little change |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 103 | } |
| 104 | |
| 105 | _Self& operator++() { ++current; return *this; } |
| 106 | _Self& operator--() { --current; return *this; } |
| 107 | _Self operator++(int) { _Self __tmp = *this; ++current; return __tmp; } |
| 108 | _Self operator--(int) { _Self __tmp = *this; --current; return __tmp; } |
| 109 | _Self operator+ (difference_type n) const { return _Self(current + n); } |
| 110 | _Self& operator+= (difference_type n) { current += n; return *this; } |
| 111 | _Self operator- (difference_type n) const { return _Self(current - n); } |
| 112 | _Self& operator-= (difference_type n) { current -= n; return *this; } |
| 113 | reference operator[](difference_type n) const { return *(*this + n); } |
| 114 | |
Chris Lattner | 697954c | 2002-01-20 22:54:45 +0000 | [diff] [blame] | 115 | inline bool operator!=(const _Self &X) const { return !operator==(X); } |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 116 | inline bool operator==(const _Self &X) const { return current == X.current; } |
| 117 | inline bool operator< (const _Self &X) const { return current < X.current; } |
| 118 | |
| 119 | inline difference_type operator-(const _Self &X) const { |
| 120 | return current - X.current; |
| 121 | } |
| 122 | }; |
| 123 | |
| 124 | template <class _Iterator, class Func> |
| 125 | inline mapped_iterator<_Iterator, Func> |
| 126 | operator+(typename mapped_iterator<_Iterator, Func>::difference_type N, |
| 127 | const mapped_iterator<_Iterator, Func>& X) { |
| 128 | return mapped_iterator<_Iterator, Func>(X.getCurrent() - N); |
| 129 | } |
| 130 | |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 131 | |
| 132 | // map_iterator - Provide a convenient way to create mapped_iterators, just like |
| 133 | // make_pair is useful for creating pairs... |
| 134 | // |
| 135 | template <class ItTy, class FuncTy> |
| 136 | inline mapped_iterator<ItTy, FuncTy> map_iterator(const ItTy &I, FuncTy F) { |
Chris Lattner | 643afb3 | 2001-09-07 16:30:28 +0000 | [diff] [blame] | 137 | return mapped_iterator<ItTy, FuncTy>(I, F); |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 138 | } |
| 139 | |
| 140 | |
Alkis Evlogimenos | bc79471 | 2004-02-14 01:17:28 +0000 | [diff] [blame] | 141 | // next/prior - These functions unlike std::advance do not modify the |
| 142 | // passed iterator but return a copy. |
| 143 | // |
| 144 | // next(myIt) returns copy of myIt incremented once |
| 145 | // next(myIt, n) returns copy of myIt incremented n times |
| 146 | // prior(myIt) returns copy of myIt decremented once |
| 147 | // prior(myIt, n) returns copy of myIt decremented n times |
| 148 | |
| 149 | template <typename ItTy, typename Dist> |
| 150 | inline ItTy next(ItTy it, Dist n) |
| 151 | { |
| 152 | std::advance(it, n); |
| 153 | return it; |
| 154 | } |
| 155 | |
| 156 | template <typename ItTy> |
| 157 | inline ItTy next(ItTy it) |
| 158 | { |
| 159 | std::advance(it, 1); |
| 160 | return it; |
| 161 | } |
| 162 | |
| 163 | template <typename ItTy, typename Dist> |
| 164 | inline ItTy prior(ItTy it, Dist n) |
| 165 | { |
| 166 | std::advance(it, -n); |
| 167 | return it; |
| 168 | } |
| 169 | |
| 170 | template <typename ItTy> |
| 171 | inline ItTy prior(ItTy it) |
| 172 | { |
| 173 | std::advance(it, -1); |
| 174 | return it; |
| 175 | } |
| 176 | |
| 177 | |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 178 | //===----------------------------------------------------------------------===// |
| 179 | // Extra additions to <algorithm> |
| 180 | //===----------------------------------------------------------------------===// |
| 181 | |
Chris Lattner | 42e018c | 2001-06-27 23:32:12 +0000 | [diff] [blame] | 182 | // apply_until - Apply a functor to a sequence continually, unless the |
| 183 | // functor returns true. Return true if the functor returned true, return false |
| 184 | // if the functor never returned true. |
| 185 | // |
| 186 | template <class InputIt, class Function> |
| 187 | bool apply_until(InputIt First, InputIt Last, Function Func) { |
| 188 | for ( ; First != Last; ++First) |
| 189 | if (Func(*First)) return true; |
| 190 | return false; |
| 191 | } |
| 192 | |
| 193 | |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 194 | // reduce - Reduce a sequence values into a single value, given an initial |
| 195 | // value and an operator. |
| 196 | // |
| 197 | template <class InputIt, class Function, class ValueType> |
| 198 | ValueType reduce(InputIt First, InputIt Last, Function Func, ValueType Value) { |
| 199 | for ( ; First != Last; ++First) |
| 200 | Value = Func(*First, Value); |
| 201 | return Value; |
| 202 | } |
| 203 | |
| 204 | #if 1 // This is likely to be more efficient |
| 205 | |
| 206 | // reduce_apply - Reduce the result of applying a function to each value in a |
| 207 | // sequence, given an initial value, an operator, a function, and a sequence. |
| 208 | // |
| 209 | template <class InputIt, class Function, class ValueType, class TransFunc> |
Chris Lattner | 42e018c | 2001-06-27 23:32:12 +0000 | [diff] [blame] | 210 | inline ValueType reduce_apply(InputIt First, InputIt Last, Function Func, |
| 211 | ValueType Value, TransFunc XForm) { |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 212 | for ( ; First != Last; ++First) |
| 213 | Value = Func(XForm(*First), Value); |
| 214 | return Value; |
| 215 | } |
| 216 | |
| 217 | #else // This is arguably more elegant |
| 218 | |
| 219 | // reduce_apply - Reduce the result of applying a function to each value in a |
| 220 | // sequence, given an initial value, an operator, a function, and a sequence. |
| 221 | // |
| 222 | template <class InputIt, class Function, class ValueType, class TransFunc> |
Chris Lattner | 42e018c | 2001-06-27 23:32:12 +0000 | [diff] [blame] | 223 | inline ValueType reduce_apply2(InputIt First, InputIt Last, Function Func, |
| 224 | ValueType Value, TransFunc XForm) { |
| 225 | return reduce(map_iterator(First, XForm), map_iterator(Last, XForm), |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 226 | Func, Value); |
| 227 | } |
| 228 | #endif |
| 229 | |
| 230 | |
Chris Lattner | 42e018c | 2001-06-27 23:32:12 +0000 | [diff] [blame] | 231 | // reduce_apply_bool - Reduce the result of applying a (bool returning) function |
| 232 | // to each value in a sequence. All of the bools returned by the mapped |
| 233 | // function are bitwise or'd together, and the result is returned. |
Chris Lattner | 3704c8c | 2001-06-25 03:54:32 +0000 | [diff] [blame] | 234 | // |
Chris Lattner | 42e018c | 2001-06-27 23:32:12 +0000 | [diff] [blame] | 235 | template <class InputIt, class Function> |
| 236 | inline bool reduce_apply_bool(InputIt First, InputIt Last, Function Func) { |
| 237 | return reduce_apply(First, Last, bitwise_or<bool>(), false, Func); |
| 238 | } |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 239 | |
Chris Lattner | 643afb3 | 2001-09-07 16:30:28 +0000 | [diff] [blame] | 240 | |
| 241 | // map - This function maps the specified input sequence into the specified |
| 242 | // output iterator, applying a unary function in between. |
| 243 | // |
| 244 | template <class InIt, class OutIt, class Functor> |
| 245 | inline OutIt mapto(InIt Begin, InIt End, OutIt Dest, Functor F) { |
| 246 | return copy(map_iterator(Begin, F), map_iterator(End, F), Dest); |
| 247 | } |
Alkis Evlogimenos | e292da2 | 2003-11-05 05:58:26 +0000 | [diff] [blame] | 248 | |
| 249 | |
| 250 | //===----------------------------------------------------------------------===// |
| 251 | // Extra additions to <utility> |
| 252 | //===----------------------------------------------------------------------===// |
| 253 | |
| 254 | // tie - this function ties two objects and returns a temporary object |
| 255 | // that is assignable from a std::pair. This can be used to make code |
| 256 | // more readable when using values returned from functions bundled in |
| 257 | // a std::pair. Since an example is worth 1000 words: |
| 258 | // |
| 259 | // typedef std::map<int, int> Int2IntMap; |
| 260 | // |
| 261 | // Int2IntMap myMap; |
| 262 | // Int2IntMap::iterator where; |
| 263 | // bool inserted; |
| 264 | // tie(where, inserted) = myMap.insert(std::make_pair(123,456)); |
| 265 | // |
| 266 | // if (inserted) |
| 267 | // // do stuff |
| 268 | // else |
| 269 | // // do other stuff |
| 270 | |
| 271 | namespace |
| 272 | { |
| 273 | template <typename T1, typename T2> |
| 274 | struct tier { |
Chris Lattner | a3f5f80 | 2003-11-13 04:11:30 +0000 | [diff] [blame] | 275 | typedef T1 &first_type; |
| 276 | typedef T2 &second_type; |
Alkis Evlogimenos | e292da2 | 2003-11-05 05:58:26 +0000 | [diff] [blame] | 277 | |
| 278 | first_type first; |
| 279 | second_type second; |
| 280 | |
| 281 | tier(first_type f, second_type s) : first(f), second(s) { } |
| 282 | tier& operator=(const std::pair<T1, T2>& p) { |
| 283 | first = p.first; |
| 284 | second = p.second; |
| 285 | return *this; |
| 286 | } |
| 287 | }; |
| 288 | } |
| 289 | |
| 290 | template <typename T1, typename T2> |
| 291 | inline tier<T1, T2> tie(T1& f, T2& s) { |
| 292 | return tier<T1, T2>(f, s); |
| 293 | } |
| 294 | |
Brian Gaeke | d0fde30 | 2003-11-11 22:41:34 +0000 | [diff] [blame] | 295 | } // End llvm namespace |
| 296 | |
Chris Lattner | 18d64ed | 2001-06-21 05:25:51 +0000 | [diff] [blame] | 297 | #endif |