I've attended optimization sessions at various conferences and all of the demos have shown IIF to be faster than IF...ENDIF.

I tried your test with VFP 6.0 SP5 and Win2000 and got the following results.

     Trial:   1       2       3       4        5      6      7      8
       IIF:  76.83   63.56   67.44   64.65     4.096  4.101  4.501  4.515
IF...ENDIF: 124.66  122.39  111.58  112.22     4.226  4.258  4.503  4.556

After the 4th trial I discovered that I had the Debug window open, that is why the tests got faster.

I also tried your test with VFP 7.0 and Win2000 and got the following results.

     Trial:  1      2      3          4      5      6          7
       IIF:  3.772  4.117  3.970      6.259  6.311  6.780      6.211
IF...ENDIF:  3.280  3.502  3.517      7.953  7.799  7.697      7.467

After trial 3 I opened the VFP 7.0 Debug window and after trial 6 I closed it.


>Kirk,
>
>I see that others have posted and said that IIF is faster than IF...ENDIF.
>
>I disagree!
>
>I remember testing this in the past and I've always found IF...ENDIF to be faster. I just ran another test using your example and as I expected, I found IF...ENDIF to be faster.
>
>Here's what I did:
>

>#DEFINE MAXLOOPS 1000000
>ldStartOn = DATE()
>lnStart = SECONDS()
>FOR x = 1 TO MAXLOOPS
>	ldStartOn = ldStartOn + IIF(VARTYPE(ldStartOn)=[D],1,86400)
>ENDFOR
>lnEnd = SECONDS()
>MESSAGEBOX('IIF: ' + TRANSFORM(lnEnd-lnStart))
>
>
>lnStart = SECONDS()
>FOR x = 1 TO MAXLOOPS
>	IF VARTYPE(ldStartOn)=[D]
>		ldStartOn=ldStartOn+1
>	ELSE
>		ldStartOn=ldStartOn+86400
>	ENDIF
>ENDFOR
>lnEnd = SECONDS()
>MESSAGEBOX('IF-ENDIF: ' + TRANSFORM(lnEnd-lnStart))
>

>
>Guy
>
>
>
>
>
>>I have a fairly large module that contains a search routine that consists of a series of Loops inside loops, inside loops. Within the loops I have serveral places where I do comparisons such as:
>>
>>

>>IF VARTYPE(ldStartOn)=[D]
>>    ldStartOn=ldStartOn+1
>>ELSE
>>    ldStartOn=ldStartOn+86400
>>ENDIF
>>

>>
>>I like the code format for readability of the IF/ELSE/ENDIF, but I'm wondering if I'm doing myself a disservice in terms of speed. This code could be replaced with a IIF(). Since this module I'm looking at runs potientially 100+ times before it exits, I thought I might want to find out which way was better in terms of speed.
>>
>>Thanks for any input.
>>
>>Kirk