git.distorted.org.uk Git - u/mdw/catacomb/blob - math/field.c

   1 /* -*-c-*-
   2  *
   3  * Abstract field operations
   4  *
   5  * (c) 2001 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of Catacomb.
  11  *
  12  * Catacomb is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU Library General Public License as
  14  * published by the Free Software Foundation; either version 2 of the
  15  * License, or (at your option) any later version.
  16  *
  17  * Catacomb is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU Library General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Library General Public
  23  * License along with Catacomb; if not, write to the Free
  24  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  25  * MA 02111-1307, USA.
  26  */
  27
  28 /*----- Header files ------------------------------------------------------*/
  29
  30 #include "field.h"
  31 #include "mp.h"
  32
  33 /*----- Main code ---------------------------------------------------------*/
  34
  35 /* --- @field_id@ --- *
  36  *
  37  * Arguments:   @field *f@ = pointer to a field
  38  *              @mp *d@ = a destination element
  39  *              @mp *x@ = a source element
  40  *
  41  * Returns:     The result element.
  42  *
  43  * Use:         An identity operation which can be used if your field has no
  44  *              internal representation.
  45  */
  46
  47 mp *field_id(field *f, mp *d, mp *x)
  48   { x = MP_COPY(x); if (d) MP_DROP(d); return (x); }
  49
  50 /* --- @field_samep@ --- *
  51  *
  52  * Arguments:   @field *f, *g@ = two fields
  53  *
  54  * Returns:     Nonzero if the fields are identical (not just isomorphic).
  55  *
  56  * Use:         Checks for sameness of fields.  This function does the full
  57  *              check, not just the field-type-specific check done by the
  58  *              @sampep@ field operation.
  59  */
  60
  61 int field_samep(field *f, field *g)
  62   { return (f == g || (f->ops == g->ops && F_SAMEP(f, g))); }
  63
  64 /* --- @field_stdsamep@ --- *
  65  *
  66  * Arguments:   @field *f, *g@ = two fields
  67  *
  68  * Returns:     Nonzero if the fields are identical (not just isomorphic).
  69  *
  70  * Use:         Standard sameness check, based on equality of the @m@
  71  *              member.
  72  */
  73
  74 int field_stdsamep(field *f, field *g) { return (MP_EQ(f->m, g->m)); }
  75
  76 /*----- That's all, folks -------------------------------------------------*/