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Morthawt

Any way to "delete" a variable? aka make it as if it never existed or was defined?

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FireFox

Hi,

It's not possible.

IMO, using IsDeclared in your code is not a good coding practice it's better to first initialize your variable and then re-initialize it and/or check for it's initializer when needed.

 

Local $sMyVar = "" ;initializer

$sMyVar = "toto"

If $sMyVar = "" Then ;not "declared"
    ;dostuff
EndIf

Local $aMyArray = 0

Local $aMyArray[3] = [0, 1, 2]

If $aMyArray = 0 Then ...
;etc
Br, FireFox. Edited by FireFox

 

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Morthawt

The reason I asked about this is it was part of an idea I had about potentially testing the method of using variables as an array substitute to see how it would compare. Part of that idea was using IsDeclared as part of some kind of counting function to update $variable_0_ which would contain the number of emulated "elements". Even if a variable is set to "" it shows up on IsDeclared, so I was wondering about a way to make a variable cease to exist so that it would not appear on IsDeclared

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jchd

Comparative timings have been made available long ago on this forum. Search may help you find it out.

AFAIK the only time where a variable "disappears" is when a local variable gets out of scope.


This wonderful site allows debugging and testing regular expressions (many flavors available). An absolute must have in your bookmarks.
Another excellent RegExp tutorial. Don't forget downloading your copy of up-to-date pcretest.exe and pcregrep.exe here
RegExp tutorial: enough to get started
PCRE v8.33 regexp documentation latest available release and currently implemented in AutoIt beta.

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SQL tutorial (covers "generic" SQL, but most of it applies to SQLite as well)
A work-in-progress SQLite3 tutorial. Don't miss other LxyzTHW pages!
SQLite official website with full documentation (may be newer than the SQLite library that comes standard with AutoIt)

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jchd

In which case they are two distinct variables which happen to carry the same name. Just like there must exist more than one John Smith on Earth, each with different lifespan expectation.


This wonderful site allows debugging and testing regular expressions (many flavors available). An absolute must have in your bookmarks.
Another excellent RegExp tutorial. Don't forget downloading your copy of up-to-date pcretest.exe and pcregrep.exe here
RegExp tutorial: enough to get started
PCRE v8.33 regexp documentation latest available release and currently implemented in AutoIt beta.

SQLitespeed is another feature-rich premier SQLite manager (includes import/export). Well worth a try.
SQLite Expert (freeware Personal Edition or payware Pro version) is a very useful SQLite database manager.
An excellent eBook covering almost every aspect of SQLite3: a must-read for anyone doing serious work.
SQL tutorial (covers "generic" SQL, but most of it applies to SQLite as well)
A work-in-progress SQLite3 tutorial. Don't miss other LxyzTHW pages!
SQLite official website with full documentation (may be newer than the SQLite library that comes standard with AutoIt)

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czardas

Here's an example of mine which (potentailly) pushes local variable creation to the limit: >_ArrayUniqueConcatenate. It may be of interest. You generally don't need to use Global variables, at least most of the time.

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guinness

You generally don't need to use Global variables, at least most of the time.

Here here.

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