------------------------------------------------------------------------------ -- -- -- GNAT LIBRARY COMPONENTS -- -- -- -- A D A . C O N T A I N E R S . P R I M E _ N U M B E R S -- -- -- -- S p e c -- -- -- -- Copyright (C) 2004-2018, Free Software Foundation, Inc. -- -- -- -- 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- -- -- ware Foundation; either version 3, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. -- -- -- -- As a special exception under Section 7 of GPL version 3, you are granted -- -- additional permissions described in the GCC Runtime Library Exception, -- -- version 3.1, as published by the Free Software Foundation. -- -- -- -- You should have received a copy of the GNU General Public License and -- -- a copy of the GCC Runtime Library Exception along with this program; -- -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- -- . -- -- -- -- This unit was originally developed by Matthew J Heaney. -- ------------------------------------------------------------------------------ -- This package declares the prime numbers array used to implement hashed -- containers. Bucket arrays are always allocated with a prime-number -- length (computed using To_Prime below), as this produces better scatter -- when hash values are folded. package Ada.Containers.Prime_Numbers is pragma Pure; type Primes_Type is array (Positive range <>) of Hash_Type; Primes : constant Primes_Type := (53, 97, 193, 389, 769, 1543, 3079, 6151, 12289, 24593, 49157, 98317, 196613, 393241, 786433, 1572869, 3145739, 6291469, 12582917, 25165843, 50331653, 100663319, 201326611, 402653189, 805306457, 1610612741, 3221225473, 4294967291); function To_Prime (Length : Count_Type) return Hash_Type; -- Returns the smallest value in Primes not less than Length end Ada.Containers.Prime_Numbers;