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1 ------------------------------------------------------------------------------
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2 -- --
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3 -- GNAT LIBRARY COMPONENTS --
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4 -- --
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5 -- A D A . C O N T A I N E R S . H A S H E D _ S E T S --
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6 -- --
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7 -- S p e c --
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8 -- --
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145
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9 -- Copyright (C) 2004-2019, Free Software Foundation, Inc. --
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111
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10 -- --
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11 -- This specification is derived from the Ada Reference Manual for use with --
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12 -- GNAT. The copyright notice above, and the license provisions that follow --
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13 -- apply solely to the contents of the part following the private keyword. --
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14 -- --
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15 -- GNAT is free software; you can redistribute it and/or modify it under --
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16 -- terms of the GNU General Public License as published by the Free Soft- --
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17 -- ware Foundation; either version 3, or (at your option) any later ver- --
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18 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
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19 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
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20 -- or FITNESS FOR A PARTICULAR PURPOSE. --
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21 -- --
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22 -- As a special exception under Section 7 of GPL version 3, you are granted --
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23 -- additional permissions described in the GCC Runtime Library Exception, --
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24 -- version 3.1, as published by the Free Software Foundation. --
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25 -- --
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26 -- You should have received a copy of the GNU General Public License and --
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27 -- a copy of the GCC Runtime Library Exception along with this program; --
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28 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
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29 -- <http://www.gnu.org/licenses/>. --
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30 -- --
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31 -- This unit was originally developed by Matthew J Heaney. --
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32 ------------------------------------------------------------------------------
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33
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34 with Ada.Iterator_Interfaces;
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35
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36 private with Ada.Containers.Hash_Tables;
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37 with Ada.Containers.Helpers;
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38 private with Ada.Finalization;
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39 private with Ada.Streams;
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40
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41 generic
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42 type Element_Type is private;
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43
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44 with function Hash (Element : Element_Type) return Hash_Type;
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45
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46 with function Equivalent_Elements
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47 (Left, Right : Element_Type) return Boolean;
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48
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49 with function "=" (Left, Right : Element_Type) return Boolean is <>;
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50
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51 package Ada.Containers.Hashed_Sets is
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52 pragma Annotate (CodePeer, Skip_Analysis);
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53 pragma Preelaborate;
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54 pragma Remote_Types;
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55
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56 type Set is tagged private
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57 with
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58 Constant_Indexing => Constant_Reference,
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59 Default_Iterator => Iterate,
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60 Iterator_Element => Element_Type;
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61
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62 pragma Preelaborable_Initialization (Set);
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63
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64 type Cursor is private;
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65 pragma Preelaborable_Initialization (Cursor);
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66
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67 Empty_Set : constant Set;
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68 -- Set objects declared without an initialization expression are
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69 -- initialized to the value Empty_Set.
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70
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71 No_Element : constant Cursor;
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72 -- Cursor objects declared without an initialization expression are
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73 -- initialized to the value No_Element.
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74
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75 function Has_Element (Position : Cursor) return Boolean;
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76 -- Equivalent to Position /= No_Element
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77
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78 package Set_Iterator_Interfaces is new
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79 Ada.Iterator_Interfaces (Cursor, Has_Element);
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80
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81 function "=" (Left, Right : Set) return Boolean;
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82 -- For each element in Left, set equality attempts to find the equal
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83 -- element in Right; if a search fails, then set equality immediately
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84 -- returns False. The search works by calling Hash to find the bucket in
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85 -- the Right set that corresponds to the Left element. If the bucket is
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86 -- non-empty, the search calls the generic formal element equality operator
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87 -- to compare the element (in Left) to the element of each node in the
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88 -- bucket (in Right); the search terminates when a matching node in the
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89 -- bucket is found, or the nodes in the bucket are exhausted. (Note that
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90 -- element equality is called here, not Equivalent_Elements. Set equality
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91 -- is the only operation in which element equality is used. Compare set
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92 -- equality to Equivalent_Sets, which does call Equivalent_Elements.)
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93
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94 function Equivalent_Sets (Left, Right : Set) return Boolean;
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95 -- Similar to set equality, with the difference that the element in Left is
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96 -- compared to the elements in Right using the generic formal
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97 -- Equivalent_Elements operation instead of element equality.
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98
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99 function To_Set (New_Item : Element_Type) return Set;
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100 -- Constructs a singleton set comprising New_Element. To_Set calls Hash to
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101 -- determine the bucket for New_Item.
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102
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103 function Capacity (Container : Set) return Count_Type;
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104 -- Returns the current capacity of the set. Capacity is the maximum length
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105 -- before which rehashing in guaranteed not to occur.
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106
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107 procedure Reserve_Capacity (Container : in out Set; Capacity : Count_Type);
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108 -- Adjusts the current capacity, by allocating a new buckets array. If the
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109 -- requested capacity is less than the current capacity, then the capacity
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110 -- is contracted (to a value not less than the current length). If the
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111 -- requested capacity is greater than the current capacity, then the
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112 -- capacity is expanded (to a value not less than what is requested). In
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113 -- either case, the nodes are rehashed from the old buckets array onto the
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114 -- new buckets array (Hash is called once for each existing element in
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115 -- order to compute the new index), and then the old buckets array is
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116 -- deallocated.
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117
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118 function Length (Container : Set) return Count_Type;
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119 -- Returns the number of items in the set
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120
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121 function Is_Empty (Container : Set) return Boolean;
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122 -- Equivalent to Length (Container) = 0
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123
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124 procedure Clear (Container : in out Set);
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125 -- Removes all of the items from the set
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126
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127 function Element (Position : Cursor) return Element_Type;
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128 -- Returns the element of the node designated by the cursor
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129
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130 procedure Replace_Element
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131 (Container : in out Set;
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132 Position : Cursor;
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133 New_Item : Element_Type);
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134 -- If New_Item is equivalent (as determined by calling Equivalent_Elements)
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135 -- to the element of the node designated by Position, then New_Element is
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136 -- assigned to that element. Otherwise, it calls Hash to determine the
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137 -- bucket for New_Item. If the bucket is not empty, then it calls
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138 -- Equivalent_Elements for each node in that bucket to determine whether
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139 -- New_Item is equivalent to an element in that bucket. If
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140 -- Equivalent_Elements returns True then Program_Error is raised (because
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141 -- an element may appear only once in the set); otherwise, New_Item is
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142 -- assigned to the node designated by Position, and the node is moved to
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143 -- its new bucket.
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144
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145 procedure Query_Element
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146 (Position : Cursor;
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147 Process : not null access procedure (Element : Element_Type));
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148 -- Calls Process with the element (having only a constant view) of the node
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149 -- designed by the cursor.
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150
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151 type Constant_Reference_Type
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152 (Element : not null access constant Element_Type) is private
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153 with Implicit_Dereference => Element;
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154
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155 function Constant_Reference
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156 (Container : aliased Set;
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157 Position : Cursor) return Constant_Reference_Type;
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158 pragma Inline (Constant_Reference);
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159
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160 procedure Assign (Target : in out Set; Source : Set);
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161
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162 function Copy (Source : Set; Capacity : Count_Type := 0) return Set;
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163
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164 procedure Move (Target : in out Set; Source : in out Set);
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165 -- Clears Target (if it's not empty), and then moves (not copies) the
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166 -- buckets array and nodes from Source to Target.
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167
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168 procedure Insert
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169 (Container : in out Set;
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170 New_Item : Element_Type;
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171 Position : out Cursor;
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172 Inserted : out Boolean);
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173 -- Conditionally inserts New_Item into the set. If New_Item is already in
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174 -- the set, then Inserted returns False and Position designates the node
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175 -- containing the existing element (which is not modified). If New_Item is
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176 -- not already in the set, then Inserted returns True and Position
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177 -- designates the newly-inserted node containing New_Item. The search for
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178 -- an existing element works as follows. Hash is called to determine
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179 -- New_Item's bucket; if the bucket is non-empty, then Equivalent_Elements
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180 -- is called to compare New_Item to the element of each node in that
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181 -- bucket. If the bucket is empty, or there were no equivalent elements in
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182 -- the bucket, the search "fails" and the New_Item is inserted in the set
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183 -- (and Inserted returns True); otherwise, the search "succeeds" (and
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184 -- Inserted returns False).
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185
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186 procedure Insert (Container : in out Set; New_Item : Element_Type);
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187 -- Attempts to insert New_Item into the set, performing the usual insertion
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188 -- search (which involves calling both Hash and Equivalent_Elements); if
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189 -- the search succeeds (New_Item is equivalent to an element already in the
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190 -- set, and so was not inserted), then this operation raises
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191 -- Constraint_Error. (This version of Insert is similar to Replace, but
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192 -- having the opposite exception behavior. It is intended for use when you
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193 -- want to assert that the item is not already in the set.)
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194
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195 procedure Include (Container : in out Set; New_Item : Element_Type);
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196 -- Attempts to insert New_Item into the set. If an element equivalent to
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197 -- New_Item is already in the set (the insertion search succeeded, and
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198 -- hence New_Item was not inserted), then the value of New_Item is assigned
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199 -- to the existing element. (This insertion operation only raises an
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200 -- exception if cursor tampering occurs. It is intended for use when you
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201 -- want to insert the item in the set, and you don't care whether an
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202 -- equivalent element is already present.)
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203
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204 procedure Replace (Container : in out Set; New_Item : Element_Type);
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205 -- Searches for New_Item in the set; if the search fails (because an
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206 -- equivalent element was not in the set), then it raises
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207 -- Constraint_Error. Otherwise, the existing element is assigned the value
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208 -- New_Item. (This is similar to Insert, but with the opposite exception
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209 -- behavior. It is intended for use when you want to assert that the item
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210 -- is already in the set.)
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211
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212 procedure Exclude (Container : in out Set; Item : Element_Type);
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213 -- Searches for Item in the set, and if found, removes its node from the
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214 -- set and then deallocates it. The search works as follows. The operation
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215 -- calls Hash to determine the item's bucket; if the bucket is not empty,
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216 -- it calls Equivalent_Elements to compare Item to the element of each node
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217 -- in the bucket. (This is the deletion analog of Include. It is intended
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218 -- for use when you want to remove the item from the set, but don't care
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219 -- whether the item is already in the set.)
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220
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221 procedure Delete (Container : in out Set; Item : Element_Type);
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222 -- Searches for Item in the set (which involves calling both Hash and
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223 -- Equivalent_Elements). If the search fails, then the operation raises
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224 -- Constraint_Error. Otherwise it removes the node from the set and then
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225 -- deallocates it. (This is the deletion analog of non-conditional
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226 -- Insert. It is intended for use when you want to assert that the item is
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227 -- already in the set.)
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228
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229 procedure Delete (Container : in out Set; Position : in out Cursor);
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230 -- Removes the node designated by Position from the set, and then
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231 -- deallocates the node. The operation calls Hash to determine the bucket,
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232 -- and then compares Position to each node in the bucket until there's a
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233 -- match (it does not call Equivalent_Elements).
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234
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235 procedure Union (Target : in out Set; Source : Set);
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236 -- The operation first calls Reserve_Capacity if the current capacity is
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237 -- less than the sum of the lengths of Source and Target. It then iterates
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238 -- over the Source set, and conditionally inserts each element into Target.
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239
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240 function Union (Left, Right : Set) return Set;
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241 -- The operation first copies the Left set to the result, and then iterates
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242 -- over the Right set to conditionally insert each element into the result.
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243
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244 function "or" (Left, Right : Set) return Set renames Union;
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245
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246 procedure Intersection (Target : in out Set; Source : Set);
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247 -- Iterates over the Target set (calling First and Next), calling Find to
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248 -- determine whether the element is in Source. If an equivalent element is
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249 -- not found in Source, the element is deleted from Target.
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250
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251 function Intersection (Left, Right : Set) return Set;
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252 -- Iterates over the Left set, calling Find to determine whether the
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253 -- element is in Right. If an equivalent element is found, it is inserted
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254 -- into the result set.
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255
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256 function "and" (Left, Right : Set) return Set renames Intersection;
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257
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258 procedure Difference (Target : in out Set; Source : Set);
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259 -- Iterates over the Source (calling First and Next), calling Find to
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260 -- determine whether the element is in Target. If an equivalent element is
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261 -- found, it is deleted from Target.
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262
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263 function Difference (Left, Right : Set) return Set;
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264 -- Iterates over the Left set, calling Find to determine whether the
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265 -- element is in the Right set. If an equivalent element is not found, the
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266 -- element is inserted into the result set.
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267
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268 function "-" (Left, Right : Set) return Set renames Difference;
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269
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270 procedure Symmetric_Difference (Target : in out Set; Source : Set);
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271 -- The operation first calls Reserve_Capacity if the current capacity is
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272 -- less than the sum of the lengths of Source and Target. It then iterates
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273 -- over the Source set, searching for the element in Target (calling Hash
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274 -- and Equivalent_Elements). If an equivalent element is found, it is
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275 -- removed from Target; otherwise it is inserted into Target.
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276
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277 function Symmetric_Difference (Left, Right : Set) return Set;
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278 -- The operation first iterates over the Left set. It calls Find to
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279 -- determine whether the element is in the Right set. If no equivalent
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280 -- element is found, the element from Left is inserted into the result. The
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281 -- operation then iterates over the Right set, to determine whether the
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282 -- element is in the Left set. If no equivalent element is found, the Right
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283 -- element is inserted into the result.
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284
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285 function "xor" (Left, Right : Set) return Set
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286 renames Symmetric_Difference;
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287
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288 function Overlap (Left, Right : Set) return Boolean;
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289 -- Iterates over the Left set (calling First and Next), calling Find to
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290 -- determine whether the element is in the Right set. If an equivalent
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291 -- element is found, the operation immediately returns True. The operation
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292 -- returns False if the iteration over Left terminates without finding any
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293 -- equivalent element in Right.
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294
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295 function Is_Subset (Subset : Set; Of_Set : Set) return Boolean;
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296 -- Iterates over Subset (calling First and Next), calling Find to determine
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297 -- whether the element is in Of_Set. If no equivalent element is found in
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298 -- Of_Set, the operation immediately returns False. The operation returns
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299 -- True if the iteration over Subset terminates without finding an element
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300 -- not in Of_Set (that is, every element in Subset is equivalent to an
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301 -- element in Of_Set).
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302
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303 function First (Container : Set) return Cursor;
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304 -- Returns a cursor that designates the first non-empty bucket, by
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305 -- searching from the beginning of the buckets array.
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306
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307 function Next (Position : Cursor) return Cursor;
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308 -- Returns a cursor that designates the node that follows the current one
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309 -- designated by Position. If Position designates the last node in its
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310 -- bucket, the operation calls Hash to compute the index of this bucket,
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311 -- and searches the buckets array for the first non-empty bucket, starting
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312 -- from that index; otherwise, it simply follows the link to the next node
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313 -- in the same bucket.
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314
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315 procedure Next (Position : in out Cursor);
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316 -- Equivalent to Position := Next (Position)
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317
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318 function Find
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319 (Container : Set;
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320 Item : Element_Type) return Cursor;
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321 -- Searches for Item in the set. Find calls Hash to determine the item's
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322 -- bucket; if the bucket is not empty, it calls Equivalent_Elements to
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323 -- compare Item to each element in the bucket. If the search succeeds, Find
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324 -- returns a cursor designating the node containing the equivalent element;
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325 -- otherwise, it returns No_Element.
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326
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327 function Contains (Container : Set; Item : Element_Type) return Boolean;
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328 -- Equivalent to Find (Container, Item) /= No_Element
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329
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330 function Equivalent_Elements (Left, Right : Cursor) return Boolean;
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331 -- Returns the result of calling Equivalent_Elements with the elements of
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332 -- the nodes designated by cursors Left and Right.
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333
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334 function Equivalent_Elements
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335 (Left : Cursor;
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336 Right : Element_Type) return Boolean;
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337 -- Returns the result of calling Equivalent_Elements with element of the
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338 -- node designated by Left and element Right.
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339
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340 function Equivalent_Elements
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341 (Left : Element_Type;
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342 Right : Cursor) return Boolean;
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343 -- Returns the result of calling Equivalent_Elements with element Left and
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344 -- the element of the node designated by Right.
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345
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346 procedure Iterate
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347 (Container : Set;
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348 Process : not null access procedure (Position : Cursor));
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349 -- Calls Process for each node in the set
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350
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351 function Iterate
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352 (Container : Set) return Set_Iterator_Interfaces.Forward_Iterator'Class;
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353
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354 generic
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355 type Key_Type (<>) is private;
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356
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357 with function Key (Element : Element_Type) return Key_Type;
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358
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359 with function Hash (Key : Key_Type) return Hash_Type;
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360
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361 with function Equivalent_Keys (Left, Right : Key_Type) return Boolean;
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362
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363 package Generic_Keys is
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364
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365 function Key (Position : Cursor) return Key_Type;
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366 -- Applies generic formal operation Key to the element of the node
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367 -- designated by Position.
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368
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369 function Element (Container : Set; Key : Key_Type) return Element_Type;
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370 -- Searches (as per the key-based Find) for the node containing Key, and
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371 -- returns the associated element.
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372
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373 procedure Replace
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374 (Container : in out Set;
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375 Key : Key_Type;
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376 New_Item : Element_Type);
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377 -- Searches (as per the key-based Find) for the node containing Key, and
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378 -- then replaces the element of that node (as per the element-based
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379 -- Replace_Element).
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380
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381 procedure Exclude (Container : in out Set; Key : Key_Type);
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382 -- Searches for Key in the set, and if found, removes its node from the
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383 -- set and then deallocates it. The search works by first calling Hash
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384 -- (on Key) to determine the bucket; if the bucket is not empty, it
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385 -- calls Equivalent_Keys to compare parameter Key to the value of
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386 -- generic formal operation Key applied to element of each node in the
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387 -- bucket.
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388
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389 procedure Delete (Container : in out Set; Key : Key_Type);
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390 -- Deletes the node containing Key as per Exclude, with the difference
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391 -- that Constraint_Error is raised if Key is not found.
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392
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393 function Find (Container : Set; Key : Key_Type) return Cursor;
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394 -- Searches for the node containing Key, and returns a cursor
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395 -- designating the node. The search works by first calling Hash (on Key)
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396 -- to determine the bucket. If the bucket is not empty, the search
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397 -- compares Key to the element of each node in the bucket, and returns
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398 -- the matching node. The comparison itself works by applying the
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399 -- generic formal Key operation to the element of the node, and then
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400 -- calling generic formal operation Equivalent_Keys.
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401
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402 function Contains (Container : Set; Key : Key_Type) return Boolean;
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403 -- Equivalent to Find (Container, Key) /= No_Element
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404
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405 procedure Update_Element_Preserving_Key
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406 (Container : in out Set;
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407 Position : Cursor;
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408 Process : not null access
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409 procedure (Element : in out Element_Type));
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410 -- Calls Process with the element of the node designated by Position,
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411 -- but with the restriction that the key-value of the element is not
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412 -- modified. The operation first makes a copy of the value returned by
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413 -- applying generic formal operation Key on the element of the node, and
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414 -- then calls Process with the element. The operation verifies that the
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415 -- key-part has not been modified by calling generic formal operation
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416 -- Equivalent_Keys to compare the saved key-value to the value returned
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417 -- by applying generic formal operation Key to the post-Process value of
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418 -- element. If the key values compare equal then the operation
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419 -- completes. Otherwise, the node is removed from the set and
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420 -- Program_Error is raised.
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421
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422 type Reference_Type (Element : not null access Element_Type) is private
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423 with Implicit_Dereference => Element;
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424
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425 function Reference_Preserving_Key
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426 (Container : aliased in out Set;
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427 Position : Cursor) return Reference_Type;
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428
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429 function Constant_Reference
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430 (Container : aliased Set;
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431 Key : Key_Type) return Constant_Reference_Type;
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432
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433 function Reference_Preserving_Key
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434 (Container : aliased in out Set;
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435 Key : Key_Type) return Reference_Type;
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436
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437 private
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438 use Ada.Streams;
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439 type Set_Access is access all Set;
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440 for Set_Access'Storage_Size use 0;
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441
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442 -- Key_Preserving references must carry information to allow removal
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443 -- of elements whose value may have been altered improperly, i.e. have
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444 -- been given values incompatible with the hash-code of the previous
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445 -- value, and are thus in the wrong bucket. (RM 18.7 (96.6/3))
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446
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447 -- We cannot store the key directly because it is an unconstrained type.
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448 -- To avoid using additional dynamic allocation we store the old cursor
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449 -- which simplifies possible removal. This is not possible for some
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450 -- other set types.
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451
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452 -- The mechanism is different for Update_Element_Preserving_Key, as
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453 -- in that case the check that buckets have not changed is performed
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454 -- at the time of the update, not when the reference is finalized.
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455
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456 package Impl is new Helpers.Generic_Implementation;
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457
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458 type Reference_Control_Type is
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459 new Impl.Reference_Control_Type with
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460 record
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461 Container : Set_Access;
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462 Index : Hash_Type;
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463 Old_Pos : Cursor;
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464 Old_Hash : Hash_Type;
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465 end record;
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466
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467 overriding procedure Finalize (Control : in out Reference_Control_Type);
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468 pragma Inline (Finalize);
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469
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470 type Reference_Type (Element : not null access Element_Type) is record
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471 Control : Reference_Control_Type;
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472 end record;
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473
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474 procedure Read
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475 (Stream : not null access Root_Stream_Type'Class;
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476 Item : out Reference_Type);
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477
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|
478 for Reference_Type'Read use Read;
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479
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480 procedure Write
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481 (Stream : not null access Root_Stream_Type'Class;
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482 Item : Reference_Type);
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483
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484 for Reference_Type'Write use Write;
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|
485 end Generic_Keys;
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486
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|
487 private
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488 pragma Inline (Next);
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|
|
489
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490 type Node_Type;
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|
|
491 type Node_Access is access Node_Type;
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492
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|
|
493 type Node_Type is limited record
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|
494 Element : aliased Element_Type;
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|
|
495 Next : Node_Access;
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|
496 end record;
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|
497
|
|
|
498 package HT_Types is
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|
499 new Hash_Tables.Generic_Hash_Table_Types (Node_Type, Node_Access);
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500
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|
501 type Set is new Ada.Finalization.Controlled with record
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|
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502 HT : HT_Types.Hash_Table_Type;
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|
503 end record;
|
|
|
504
|
|
|
505 overriding procedure Adjust (Container : in out Set);
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506
|
|
|
507 overriding procedure Finalize (Container : in out Set);
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|
|
508
|
|
|
509 use HT_Types, HT_Types.Implementation;
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|
|
510 use Ada.Finalization;
|
|
|
511 use Ada.Streams;
|
|
|
512
|
|
|
513 procedure Write
|
|
|
514 (Stream : not null access Root_Stream_Type'Class;
|
|
|
515 Container : Set);
|
|
|
516
|
|
|
517 for Set'Write use Write;
|
|
|
518
|
|
|
519 procedure Read
|
|
|
520 (Stream : not null access Root_Stream_Type'Class;
|
|
|
521 Container : out Set);
|
|
|
522
|
|
|
523 for Set'Read use Read;
|
|
|
524
|
|
|
525 type Set_Access is access all Set;
|
|
|
526 for Set_Access'Storage_Size use 0;
|
|
|
527
|
|
|
528 type Cursor is record
|
|
|
529 Container : Set_Access;
|
|
|
530 Node : Node_Access;
|
|
|
531 Position : Hash_Type := Hash_Type'Last;
|
|
|
532 end record;
|
|
|
533
|
|
|
534 procedure Write
|
|
|
535 (Stream : not null access Root_Stream_Type'Class;
|
|
|
536 Item : Cursor);
|
|
|
537
|
|
|
538 for Cursor'Write use Write;
|
|
|
539
|
|
|
540 procedure Read
|
|
|
541 (Stream : not null access Root_Stream_Type'Class;
|
|
|
542 Item : out Cursor);
|
|
|
543
|
|
|
544 for Cursor'Read use Read;
|
|
|
545
|
|
|
546 subtype Reference_Control_Type is Implementation.Reference_Control_Type;
|
|
|
547 -- It is necessary to rename this here, so that the compiler can find it
|
|
|
548
|
|
|
549 type Constant_Reference_Type
|
|
|
550 (Element : not null access constant Element_Type) is
|
|
|
551 record
|
|
|
552 Control : Reference_Control_Type :=
|
|
|
553 raise Program_Error with "uninitialized reference";
|
|
|
554 -- The RM says, "The default initialization of an object of
|
|
|
555 -- type Constant_Reference_Type or Reference_Type propagates
|
|
|
556 -- Program_Error."
|
|
|
557 end record;
|
|
|
558
|
|
|
559 procedure Read
|
|
|
560 (Stream : not null access Root_Stream_Type'Class;
|
|
|
561 Item : out Constant_Reference_Type);
|
|
|
562
|
|
|
563 for Constant_Reference_Type'Read use Read;
|
|
|
564
|
|
|
565 procedure Write
|
|
|
566 (Stream : not null access Root_Stream_Type'Class;
|
|
|
567 Item : Constant_Reference_Type);
|
|
|
568
|
|
|
569 for Constant_Reference_Type'Write use Write;
|
|
|
570
|
|
|
571 -- Three operations are used to optimize in the expansion of "for ... of"
|
|
|
572 -- loops: the Next(Cursor) procedure in the visible part, and the following
|
|
|
573 -- Pseudo_Reference and Get_Element_Access functions. See Sem_Ch5 for
|
|
|
574 -- details.
|
|
|
575
|
|
|
576 function Pseudo_Reference
|
|
|
577 (Container : aliased Set'Class) return Reference_Control_Type;
|
|
|
578 pragma Inline (Pseudo_Reference);
|
|
|
579 -- Creates an object of type Reference_Control_Type pointing to the
|
|
|
580 -- container, and increments the Lock. Finalization of this object will
|
|
|
581 -- decrement the Lock.
|
|
|
582
|
|
|
583 type Element_Access is access all Element_Type with
|
|
|
584 Storage_Size => 0;
|
|
|
585
|
|
|
586 function Get_Element_Access
|
|
|
587 (Position : Cursor) return not null Element_Access;
|
|
|
588 -- Returns a pointer to the element designated by Position.
|
|
|
589
|
|
|
590 Empty_Set : constant Set := (Controlled with others => <>);
|
|
|
591
|
|
|
592 No_Element : constant Cursor :=
|
|
|
593 (Container => null, Node => null, Position => Hash_Type'Last);
|
|
|
594
|
|
|
595 type Iterator is new Limited_Controlled and
|
|
|
596 Set_Iterator_Interfaces.Forward_Iterator with
|
|
|
597 record
|
|
|
598 Container : Set_Access;
|
|
|
599 end record
|
|
|
600 with Disable_Controlled => not T_Check;
|
|
|
601
|
|
|
602 overriding function First (Object : Iterator) return Cursor;
|
|
|
603
|
|
|
604 overriding function Next
|
|
|
605 (Object : Iterator;
|
|
|
606 Position : Cursor) return Cursor;
|
|
|
607 overriding procedure Finalize (Object : in out Iterator);
|
|
|
608
|
|
|
609 end Ada.Containers.Hashed_Sets;
|
