REFBit.mesa
Copyright © 1984 by Xerox Corporation. All rights reserved.
Last edited by Curry, September 21, 1985 4:26:32 pm PDT
This package provides bit level access to the values behind Cedar REFs. `Error' will be raised if you try to twiddle refs, pointers or other non-vanilla items in this way.
DIRECTORY
AMBridge USING [WordSequence],
AMTypes USING [TV, Type],
IO USING [],
Rope USING [ROPE];
REFBit: CEDAR DEFINITIONS =
BEGIN
Error: ERROR [msg: ROPE];
REFBitDesc:  TYPE = REF REFBitDescRec;
REFBitDescRec: TYPE = RECORD [
typeName: ROPE,
tv:    TV,
wds:   WordSeq,
bitForm:  Format,
fieldForm: Format ];
Format:     TYPE = REF FormatSeq;
FormatSeq:   TYPE = RECORD[SEQUENCE size: CARDINAL OF FormatRec];
FormatList:   TYPE = LIST OF FormatRec;
FormatRec:   TYPE = RECORD[
name:  ROPE,
nameInv: ROPE,
type:  Type,
firstBit: CARDINAL,
bitSize: CARDINAL ];
WordSeq:   TYPE = AMBridge.WordSequence;
ROPE:    TYPE = Rope.ROPE;
TV:     TYPE = AMTypes.TV;
Type:     TYPE = AMTypes.Type;
The Basics - all you really need to get and set bits inside REFs
Size: PROC[ref: REF]        RETURNS [index: INT];
Get: PROC[ref: REF, index: INT]     RETURNS [val: BOOL];
Set: PROC[ref: REF, index: INT, val: BOOL];
Extra stuff handy for speed, formats, names, printing etc.
ResetCache:  PROC;
Desc:     PROC[ref: REF]         RETURNS [desc: REFBitDesc];
BitNameList:  PROC[ref: REF, both: BOOL]     RETURNS [list: LIST OF ROPE];
NEWFromName: PROC[record: ROPE]        RETURNS [ref: REF];
DescWdsToTV: PROC[desc: REFBitDesc];
TVToDescWds: PROC[desc: REFBitDesc];
FormatListing:  PROC[record: REF, bitLevel: BOOLFALSE] RETURNS [listing: ROPE];
END.