I hadn't really played much with RAID/VLIST, so I guess this is my springboard..
VLISTING the WHILE/DO vs IF THEN yielded some interesting results WHILE/DO 00003 00006 : 1C2 vec_add CTR 1 => CTR 00005 0000E : 10C nop 00005 00010 : 0DC lt CTR 4 => $R0 00005 00018 : 2DE testfw $R0 00084: 00006 00020 : 130 printcrlf CTR 00007 00026 : 1C2 vec_add CTR 1 => CTR 00008 0002E : 130 printcrlf CTR 00009 00034 : 1C2 vec_add CTR 1 => CTR IF/THEN EXIT 00003 00006 : 1C2 vec_add CTR 1 => CTR 00004 0000E : 0DC lt CTR 4 => $R0 00004 00016 : 10E not $R0 => $R1 00004 0001C : 2DE testfw $R1 0002C: 00004 00024 : 0C2 jump 00090: 00006 0002C : 130 printcrlf CTR 00007 00032 : 1C2 vec_add CTR 1 => CTR 00008 0003A : 130 printcrlf CTR Seems the IF/THEN EXIT adds a few extra opcodes in, but in general it's pretty much the same effect. So with large loops (many records) it might slow the process down a couple seconds. George > -----Original Message----- > From: [email protected] [mailto:owner-u2- > [email protected]] On Behalf Of George Gallen > Sent: Friday, February 27, 2009 11:20 AM > To: Ardent > Subject: [U2] DO/WHILE vs IF THEN > > OK Aside from programming styles > > Is there any "functional" difference between > > WHILE expression DO and IF NOT(expression) THEN EXIT > and > UNTIL expression DO and IF expression THEN EXIT > > > First I thought that the DO/WHILE would activate as soon as > the condition occurred and drop out of a loop, but that is not > the case, the condition has to be active AND control has to be > back at the WHILE statement. > > > Example: > > 0001: CTR=0 > 0002: LOOP > 0003: CTR=CTR+1 > 0004: WHILE CTR<4 DO > 0005: PRINT CTR > 0006: CTR=CTR+1 > 0007: PRINT CTR > 0008: CTR=CTR+1 > 0009: PRINT CTR > 0010: CTR=CTR+1 > 0011: PRINT CTR > 0012: CTR=CTR+1 > 0013: PRINT CTR > 0014: CTR=CTR+1 > 0015: PRINT CTR > 0016: CTR=CTR+1 > 0017: PRINT CTR > 0018: REPEAT > 0019: STOP > 0020: END > > My first thought was that once CTR = 5, the loop would end (at LINE 12) > but it > didn't > until control was passed back to LINE 4, then it ended. > ------- > u2-users mailing list > [email protected] > To unsubscribe please visit http://listserver.u2ug.org/ ------- u2-users mailing list [email protected] To unsubscribe please visit http://listserver.u2ug.org/
