Do or don't do

[stecxjo]

I seem to recall that at one time you could put a LiveCode script into a field's contents and then run that script with the "do" command:

on mouseUp
do fld 1
end mouseUp

It would be one way of showing a script in a field and then using a button to show what that script can do....

Or am I disremembering here?

--Steve

[Klaus]

Hi Steve,

yes, you can still DO something like this!
A tiny test would have answered this question

But there is a limit what you can DO, check "scriptlimits" in the dictionary!
And keep in mind that this might be up to 30 times slower than a "regular" script.


Best

Klaus

[dunbarx]

Steve.

I read that the scriptLimits only applies to standalones. Just a comment. I could be wrong. But I wonder, why do you want to do it that way?

Klaus, about the speed thing? I tried this in a field:

Code: Select all

put the ticks into temp
put 0 into accum
repeat 1000000
add 1 to accum
end repeat
answer the ticks - temp

and then in a button:

Code: Select all

on mouseUp
   do fld 1

   --   get fld 1  --just a test, no difference
   --   do it
end mouseUp

No difference in time between all that "doing" and just putting the original script into a button.

Craig

[Klaus]

Hi Craig,

oh yes, this only applies to standalones!

And execution speed surely depends on the complexity of the script.
Your repeat loop is not very complex per se


Best

Klaus

[sturgis]

And the repeat is in the do script so do is only called to compile 1 time. Should be very fast. If instead do was called 1000000 times I suspect the difference (in a standalone) would be quite noticeable. Doing a curiosity test right now, but think I should have done less loops! *twiddles thumbs*

EDIT: First test results back. Using do 51017 millisec. Non-do 1706

Still waiting on the other.

Code: Select all

on mouseUp
   put the milliseconds into tStart1
   repeat 10000000 times -- do method
      do field 1
   end repeat
   put the milliseconds into tEnd1

   put the milliseconds into tStart2
   repeat 10000000 times -- non-do method
      put random(100000) into tDummy2 -- same thing is in the field
   end repeat
   put the milliseconds into tEnd2
   
   answer merge("Do method: [[tend1 - tstart1]] non do method: [[tend2 - tstart2]]")
end mouseUp

[dunbarx]

And the repeat is in the do script so do is only called to compile 1 time. Should be very fast. If instead do was called 1000000 times

I certainly agree with that, but when would "do" be called more than once?

If even once?

Ah, but Steve is thinking about being able to see a script right in front of the user, and then invoking it, as opposed to having to open the editor and dig around.

I had asked why anyone would want to execute a script from a field, and think that this is a very reasonable, er, reason.

Craig

[sturgis]

Well true, and for that use its perfect.

I don't recall seeing this in the kickstart info but.. do you know if the scriptlimits will be removed in lcfree?

[stecxjo]

Thanks for the comments. I am using the field to show example code, for instance, how to use a variable within a repeat loop. It's really just for demo purposes. Of course, I can put the code also into a button to demonstrate, but I want my students to see the difference between doing something with ten lines of code vs just a few lines of code using repeat loops and variables.

I did try this out, Klaus, and what I found was that the DO didn't do what I thought the DO did. It didn't work. And this was not within a standalone, but in a stack that I'm currently putting together.

I discovered why it wasn't working, though. I had copied the mouseUp handler into the field as well and that just confused the hell out of the DO command.

I got DOO-DOO when it wouldn't do Do.

--Steve

[Klaus]

Hi Steve,

and don't forget that even the "Dodo" bird has died out along time ago:
http://en.wikipedia.org/wiki/Dodo




Best

Klaus

[andrewferguson]

Hi,
The 10 line script limits will be removed from standalone applications built with the open source version of LiveCode.
Andrew