VariantRecords.mesa
Copyright Ó 1991, 1992 by Xerox Corporation. All rights reserved.
Sturgis, November 20, 1988
Sturgis, December 12, 1988 3:50:07 pm PST
Last changed by Theimer on July 16, 1989 4:36:43 pm PDT
Spreitze, May 21, 1991 8:38 am PDT
Laurie Horton, January 29, 1992 9:42 am PST
VariantRecords:
CEDAR
DEFINITIONS =
BEGIN
Type: TYPE = CirioTypes.Type;
Mem: TYPE = CirioTypes.Mem;
Node: TYPE = CirioTypes.Node;
CC: TYPE = CirioTypes.CompilerContext;
The preamble type is expected to behave like a FieldList type.
The tag type is expected to be an Enumerated type.
The tail types are expected to be Record or VariantRecord types.
index is in [0..nTailTypes)
CreateVariantRecordType:
PROC[preamble: Type, tailName: Rope.
ROPE, tagName: Rope.
ROPE, tagType: Type, nTailTypes:
INT, controlled:
BOOL, details: VariantRecordTypeDetails, cc:
CC, procData:
REF
ANY]
RETURNS[Type];
CCTypes.GetTypeRepresentation will return procData.
VariantRecordTypeDetails: TYPE ~ REF VariantRecordTypeDetailsRec;
VariantRecordTypeDetailsRec:
TYPE ~
RECORD [
createIndirectNode: PROC [cc: CC, procData: REF ANY, indirectType, targetType: Type, mem: Mem] RETURNS [Node],
getBitSize: PROC[indirectType: Type, cc: CC, procData: REF ANY] RETURNS[CARD],
getTailType: PROC[index: INT, procData: REF ANY] RETURNS[Type]
];
maybe this should be a CRTypes object action?
GetVRVariant: PROC[vrType: Type, index: INT, cc: CC] RETURNS[Type];
IndirectVRNodeProcs:
TYPE =
RECORD[
selectPreamble: PROC[procsData: REF ANY, cc: CC] RETURNS[Node],
readVariantIndex: PROC[procsData: REF ANY, cc: CC] RETURNS[INT],
selectTag: PROC[procsData: REF ANY, cc: CC] RETURNS[Node],
selectTailBody: PROC[procsData: REF ANY, cc: CC] RETURNS[Node],
getPointer: PROC[procsData: REF ANY, cc: CC] RETURNS[Node]];
VariantRecordNodeProcs:
TYPE =
RECORD[
extractPreamble: PROC[procsData: REF ANY, cc: CC] RETURNS[Node],
variantIndex: PROC[procsData: REF ANY, cc: CC] RETURNS[INT],
extractTag: PROC[procsData: REF ANY, cc: CC] RETURNS[Node],
extractTailBody: PROC[procsData: REF ANY, cc: CC] RETURNS[Node]];
CreateIndirectVariantRecordNode: PROC[vrType: Type, procs: REF IndirectVRNodeProcs, procsData: REF ANY, cc: CC] RETURNS[Node];
CreateVariantRecordNode: PROC[type: Type, procs: REF VariantRecordNodeProcs, procsData: REF ANY, cc: CC, alreadyLoaded: BOOLEAN ← FALSE] RETURNS[Node];