CardTable.Mesa
Copyright © 1985 by Xerox Corporation. All rights reserved.
Doug Terry October 15, 1985 5:44:11 pm PDT
Like RefTab.mesa except uses LONG CARDINALs as keys.
CardTable: CEDAR DEFINITIONS = BEGIN
Ref: TYPE = REF CardTableRep;
CardTableRep: PUBLIC TYPE = MONITORED RECORD [mod: CARDINAL, size: INT, data: REF Seq];
Seq: TYPE = RECORD[nodes: SEQUENCE max: SeqIndex OF Node];
SeqIndex: TYPE = CARDINAL[0..4000);
Node: TYPE = REF NodeRep;
NodeRep: TYPE = RECORD [key: Key, val: Val, next: Node];
Key: TYPE = LONG CARDINAL;
Val: TYPE = REF;
Create: PROC [mod: SeqIndex ← 17] RETURNS [Ref];
creates new table with suggested hash size
GetSize: PROC [x: Ref] RETURNS [INT];
returns number of key-value pairs in table
Fetch: PROC [x: Ref, key: Key] RETURNS [found: BOOLEAN, val: Val];
looks up key in table, returns associated value (if any)
if found is TRUE, val is value associated with given key
if found is FALSE, val is NIL
Replace: PROC [x: Ref, key: Key, val: Val] RETURNS [BOOLEAN];
returns TRUE after overwriting old value for existing key-value pair
if no previous value for key, returns FALSE without inserting new pair
Store: PROC [x: Ref, key: Key, val: Val] RETURNS [BOOLEAN];
returns TRUE after inserting new pair
returns FALSE after overwriting old value for existing key-value pair
Insert: PROC [x: Ref, key: Key, val: Val] RETURNS [BOOLEAN];
returns TRUE after inserted new pair
if previous value existed for key, returns FALSE without changing value
Delete: PROC [x: Ref, key: Key] RETURNS [BOOLEAN];
deletes key-value pair associated with given key
returns TRUE if deletion actually occurred, FALSE if no such key
Pairs: PROC [x: Ref, action: EachPairAction] RETURNS [BOOLEAN];
enumerates pairs currently in symbol table in unspecified order
pairs inserted/deleted during enumeration may or may not be seen
applies action to each pair until action returns TRUE or no more pairs
returns TRUE if some action returns TRUE
EachPairAction: TYPE = PROC [key: Key, val: Val] RETURNS [quit: BOOLEAN];
END.