diff options
Diffstat (limited to 'src/include/nodes/pg_list.h')
| -rw-r--r-- | src/include/nodes/pg_list.h | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/src/include/nodes/pg_list.h b/src/include/nodes/pg_list.h index b48fc02e855..bc42917a355 100644 --- a/src/include/nodes/pg_list.h +++ b/src/include/nodes/pg_list.h @@ -7,7 +7,7 @@ * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $Id: pg_list.h,v 1.35 2003/02/09 06:56:28 tgl Exp $ + * $Id: pg_list.h,v 1.36 2003/05/28 22:32:50 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -129,6 +129,21 @@ typedef struct List #define makeListo2(x1,x2) lconso(x1, makeListo1(x2)) /* + * FastList is an optimization for building large lists. The conventional + * way to build a list is repeated lappend() operations, but that is O(N^2) + * in the number of list items, which gets tedious for large lists. + */ +typedef struct FastList +{ + List *head; + List *tail; +} FastList; + +#define FastListInit(fl) ( (fl)->head = (fl)->tail = NIL ) +#define FastListValue(fl) ( (fl)->head ) + + +/* * function prototypes in nodes/list.c */ extern Value *makeInteger(long i); @@ -143,6 +158,11 @@ extern List *lappend(List *list, void *datum); extern List *lappendi(List *list, int datum); extern List *lappendo(List *list, Oid datum); extern List *nconc(List *list1, List *list2); +extern void FastAppend(FastList *fl, void *datum); +extern void FastAppendi(FastList *fl, int datum); +extern void FastAppendo(FastList *fl, Oid datum); +extern void FastConc(FastList *fl, List *cells); +extern void FastConcFast(FastList *fl, FastList *fl2); extern void *nth(int n, List *l); extern int length(List *list); extern void *llast(List *list); |