[ANN] News Reader Stack Available

[J. Landman Gay]

On 6/19/03 1:15 AM, Dar Scott wrote:

> 
> On Wednesday, June 18, 2003, at 11:08 PM, Chipp Walters wrote:
> 
>> I'm with Jacqueline. I always thought it took the interpreter longer to
>> figure out what it's looking at.
> 
> ...
> 
>>>> Has anyone else any
>>>> thoughts on the wisdom or otherwise of quoting all names?
>>>
>>>
>>> I believe there is a slight speed hit if you don't use quotes, since the
>>> engine has to figure out whether the word is a variable or a name.
> 
> 
> A quick test on OS X seems to indicate that is not the case:
> 
> on mouseUp
>   local x
>   set the numberFormat to "0.000000"
>   put empty into field "Report"
>   put the long seconds into tEnd  -- throw this one away
>   put the long seconds into tStart
>   put the long seconds into tEnd
>   put tEnd-tStart into tCorrection
>   put the long seconds into tStart
>   put the highlight of button "dummy" into x
>   put the long seconds into tEnd
>   put (tEnd - tStart - tCorrection) & " s quoted" & LF after field "Report"
>   put the long seconds into tStart
>   put the highlight of button dummy into x
>   put the long seconds into tEnd
>   put (tEnd - tStart - tCorrection) & " s unquoted" & LF after field 
> "Report"
> end mouseUp
> 
> Typical results:
> 
> 0.000025 s quoted
> 0.000026 s unquoted
> 
> I would guess that the script compiler checks to see whether the name 
> was used as a variable so for in the script.  If it has, it would 
> compile a variable use.  If not, it would compile the same as a string.
> 
> If there is a real difference is is one or two microseconds on my computer.

I ran your script on my Mac G4/350:

0.000031 s quoted
0.000053 s unquoted

on my G4 12" PB:

0.000033 s quoted
0.000057 s unquoted

So, about twice as long if unquoted, though still not a huge amount of 
time. If the test were run on older machines, I suspect there would be 
greater variance.

This reminds me of some speed tests that a HyperCard user did a few 
years ago. The HyperCard manual gave several tips on how to improve 
performance. Using the newest Mac available at the time, he ran 
extensive tests on each tip and concluded that there were no advantages 
to using the suggested techniques. However, when I re-ran his tests on a 
few of my old Macs (one of them the original SE) there was a difference 
in speed that could be measured in seconds, and in one case, minutes.

Because I don't know what machines my users will be running, I always 
quote names. I also use a few other speed tips routinely, partly out of 
habit, but also because I never know how much difference it may make to 
my users. I suppose in this day and age it doesn't matter much any more, 
but these habits feel like good ones to me in general so I keep them.

-- 
Jacqueline Landman Gay         |     jacque at hyperactivesw.com
HyperActive Software           |     http://www.hyperactivesw.com