diff options
Diffstat (limited to 'gcc/ada/g-htable.ads')
| -rw-r--r-- | gcc/ada/g-htable.ads | 175 |
1 files changed, 4 insertions, 171 deletions
diff --git a/gcc/ada/g-htable.ads b/gcc/ada/g-htable.ads index 11f1193d121..28745520645 100644 --- a/gcc/ada/g-htable.ads +++ b/gcc/ada/g-htable.ads @@ -6,7 +6,7 @@ -- -- -- S p e c -- -- -- --- Copyright (C) 1995-2010, AdaCore -- +-- Copyright (C) 1995-2011, AdaCore -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- @@ -37,9 +37,7 @@ -- The Static_HTable package provides a more complex interface that allows -- complete control over allocation. --- Note: actual code is found in System.HTable (s-htable.ads/adb) since --- this facility is accessed from run time routines, but clients should --- always access the version supplied via GNAT.HTable. +-- See file s-htable.ads for full documentation of the interface pragma Compiler_Unit; @@ -51,177 +49,12 @@ package GNAT.HTable is -- The elaborate body is because we have a dummy body to deal with -- bootstrap path problems (we used to have a real body, and now we don't -- need it any more, but the bootstrap requires that we have a dummy body, - -- since otherwise the old body gets picked up. - - ------------------- - -- Simple_HTable -- - ------------------- - - -- A simple hash table abstraction, easy to instantiate, easy to use. - -- The table associates one element to one key with the procedure Set. - -- Get retrieves the Element stored for a given Key. The efficiency of - -- retrieval is function of the size of the Table parameterized by - -- Header_Num and the hashing function Hash. + -- since otherwise the old body gets picked up; also, we can't use pragma + -- No_Body because older bootstrap compilers don't support that). generic package Simple_HTable renames System.HTable.Simple_HTable; - - -- For convenience of reference here is what this package has in it: - - -- generic - -- type Header_Num is range <>; - -- -- An integer type indicating the number and range of hash headers - - -- type Element is private; - -- -- The type of element to be stored - - -- No_Element : Element; - -- -- The object that is returned by Get when no element has been set - -- -- for a given key - - -- type Key is private; - -- with function Hash (F : Key) return Header_Num; - -- with function Equal (F1, F2 : Key) return Boolean; - - -- package Simple_HTable is - - -- procedure Set (K : Key; E : Element); - -- -- Associates an element with a given key. Overrides any previously - -- -- associated element. - - -- procedure Reset; - -- -- Removes and frees all elements in the table - - -- function Get (K : Key) return Element; - -- -- Returns the Element associated with a key or No_Element if the - -- -- given key has not associated element - - -- procedure Remove (K : Key); - -- -- Removes the latest inserted element pointer associated with the - -- -- given key if any, does nothing if none. - - -- function Get_First return Element; - -- -- Returns No_Element if the HTable is empty, otherwise returns one - -- -- non specified element. There is no guarantee that two calls to - -- -- this function will return the same element. - - -- function Get_Next return Element; - -- -- Returns a non-specified element that has not been returned by the - -- -- same function since the last call to Get_First or No_Element if - -- -- there is no such element. If there is no call to 'Set' in between - -- -- Get_Next calls, all the elements of the HTable will be traversed. - - -- procedure Get_First (K : out Key; E : out Element); - -- -- This version of the iterator returns a key/element pair. A non- - -- -- specified entry is returned, and there is no guarantee that two - -- -- calls to this procedure will return the same element. - - -- procedure Get_Next (K : out Key; E : out Element); - -- -- This version of the iterator returns a key/element pair. It - -- -- returns a non-specified element that has not been returned since - -- -- the last call to Get_First. If there is no remaining element, - -- -- then E is set to No_Element, and the value in K is undefined. - -- -- If there is no call to Set in between Get_Next calls, all the - -- -- elements of the HTable will be traversed. - - -- end Simple_HTable; - - ------------------- - -- Static_HTable -- - ------------------- - - -- A low-level Hash-Table abstraction, not as easy to instantiate as - -- Simple_HTable but designed to allow complete control over the - -- allocation of necessary data structures. Particularly useful when - -- dynamic allocation is not desired. The model is that each Element - -- contains its own Key that can be retrieved by Get_Key. Furthermore, - -- Element provides a link that can be used by the HTable for linking - -- elements with same hash codes: - - -- Element - - -- +-------------------+ - -- | Key | - -- +-------------------+ - -- : other data : - -- +-------------------+ - -- | Next Elmt | - -- +-------------------+ - generic package Static_HTable renames System.HTable.Static_HTable; - -- For convenience of reference here is what this package has in it: - - -- generic - -- type Header_Num is range <>; - -- -- An integer type indicating the number and range of hash headers. - - -- type Element (<>) is limited private; - -- -- The type of element to be stored - - -- type Elmt_Ptr is private; - -- -- The type used to reference an element (will usually be an - -- -- access type, but could be some other form of type such as - -- -- an integer type). - - -- Null_Ptr : Elmt_Ptr; - -- -- The null value of the Elmt_Ptr type. - - -- with procedure Set_Next (E : Elmt_Ptr; Next : Elmt_Ptr); - -- with function Next (E : Elmt_Ptr) return Elmt_Ptr; - -- -- The type must provide an internal link for the sake of the - -- -- staticness of the HTable. - - -- type Key is limited private; - -- with function Get_Key (E : Elmt_Ptr) return Key; - -- with function Hash (F : Key) return Header_Num; - -- with function Equal (F1, F2 : Key) return Boolean; - - -- package Static_HTable is - - -- procedure Reset; - -- -- Resets the hash table by setting all its elements to Null_Ptr. - -- -- The effect is to clear the hash table so that it can be reused. - -- -- For the most common case where Elmt_Ptr is an access type, and - -- -- Null_Ptr is null, this is only needed if the same table is - -- -- reused in a new context. If Elmt_Ptr is other than an access - -- -- type, or Null_Ptr is other than null, then Reset must be called - -- -- before the first use of the hash table. - - -- procedure Set (E : Elmt_Ptr); - -- -- Insert the element pointer in the HTable - - -- function Get (K : Key) return Elmt_Ptr; - -- -- Returns the latest inserted element pointer with the given Key - -- -- or null if none. - - -- procedure Remove (K : Key); - -- -- Removes the latest inserted element pointer associated with the - -- -- given key if any, does nothing if none. - - -- function Get_First return Elmt_Ptr; - -- -- Returns Null_Ptr if the HTable is empty, otherwise returns one - -- -- non specified element. There is no guarantee that two calls to - -- -- this function will return the same element. - - -- function Get_Next return Elmt_Ptr; - -- -- Returns a non-specified element that has not been returned by - -- -- the same function since the last call to Get_First or Null_Ptr - -- -- if there is no such element or Get_First has never been called. - -- -- If there is no call to 'Set' in between Get_Next calls, all - -- -- the elements of the HTable will be traversed. - - -- end Static_HTable; - - ---------- - -- Hash -- - ---------- - - -- A generic hashing function working on String keys - generic function Hash renames System.HTable.Hash; - -- generic - -- type Header_Num is range <>; - -- function Hash (Key : String) return Header_Num; - end GNAT.HTable; |