Good coding practices in AutoIt

[czardas]

Dim shouldn't ever be used ...

Perhaps you could show us the preferred method for the example by Firefox and explain why it is better than using the depreciated Dim keyword.

[guinness]

czardas,

Here you are >>

#include <Array.au3>

Global $aArray[2] = [1, 2]

SomeFunc()

Func SomeFunc()
    ReDim $aArray[3] ; Re-size the array and keep its content.
    _ArrayDisplay($aArray)

    Global $aArray[2] ; Erase the contents of $aArray and re-size it.
    _ArrayDisplay($aArray)
EndFunc   ;==>SomeFunc

Edited September 4, 2015 by guinness

[czardas]

That looks so strange and weird. I also think it's odd to have Dim depreciated while not also depreciating ReDim. It's as if there are bits of the jigsaw missing.

[guinness]

Dim and ReDim are two totally different things.

[czardas]

Dim and ReDim are two totally different things.

Even so, etimology suggests at least a very strong link. I didn't like the Global declaration within your function. It seems to go against the grain. In any case I won't be needing this so it's a mute moot point to me.

Edited December 22, 2012 by czardas

[guinness]

 

I won't be needing this so it's a mute point to me.

 

OK?! So there was no need for me to respond then?

This is easier to read.

#include <Array.au3>

Global $g_aArray[2] = [1, 2]

SomeFunc()

Func SomeFunc()
    ReDim $g_aArray[3] ; Re-size the array and keep its content.
    _ArrayDisplay($g_aArray)

    Local $aArrayN[2] ; Create a new array.
    $g_aArray = $aArrayN ; Assign to the Global variable.
    $aArrayN = 0 ; Destroy array contents.
    _ArrayDisplay($g_aArray)
EndFunc   ;==>SomeFunc

Edited September 4, 2015 by guinness

[czardas]

I meant no disrespect. I would also do it differently.

How I might approach this, though I'm not sure which is best.

#include <Array.au3>

Global $aArray[2] = [1, 2]

SomeFunc()
_ArrayDisplay($aArray)

Func SomeFunc()
    ReDim $aArray[3] ; Re-size the array and keep its content.
    _ArrayDisplay($aArray)

    ReDim $aArray[1] ; Re-size to one element
    ReDim $aArray[4] ; Re-size the array
    _ArrayDelete ($aArray, 0) ; Remove the only remaining assigned value.
EndFunc   ;==>SomeFunc

Did I say mute point earlier - that should be moot point.

Edited December 22, 2012 by czardas

[AZJIO]

I generally avoid using globals like the plague.

How to make a variable visible to all functions?

Dim shouldn't ever be used.

The first option looks more compact.

#include <Array.au3>
#include <File.au3>

Global $aFiles2D
_FuncName1(@SystemDir & '\config')
_FuncName2(@SystemDir & '\config')

Func _FuncName1($sPath)
    Local $aFiles = _FileListToArray($sPath, "*.*", 1)
    If @error Then Return
    Dim $aFiles2D[$aFiles[0] + 1][2] = [[$aFiles[0] + 1]]
    For $i = 1 To $aFiles[0]
        $aFiles2D[$i][0] = $aFiles[$i]
        $tmp = FileGetAttrib(@WindowsDir & '\' & $aFiles[$i])
        If Not @error Then $aFiles2D[$i][1] = $tmp
    Next
    _ArrayDisplay($aFiles2D, 'Array')
EndFunc   ;==>_FuncName

Func _FuncName2($sPath)
    Local $aFiles = _FileListToArray($sPath, "*.*", 1)
    If @error Then Return
    ReDim $aFiles2D[1]
    ReDim $aFiles2D[$aFiles[0] + 1][2]
    $aFiles2D[0][0] = $aFiles[0] + 1
    For $i = 1 To $aFiles[0]
        $aFiles2D[$i][0] = $aFiles[$i]
        $tmp = FileGetAttrib(@WindowsDir & '\' & $aFiles[$i])
        If Not @error Then $aFiles2D[$i][1] = $tmp
    Next
    _ArrayDisplay($aFiles2D, 'Array')
EndFunc   ;==>_FuncName

[DicatoroftheUSA]

Notable mention is using prefix to indicate the type of expected variable.

.

$aStuff ;array
$sStuff ;string
$oStuff; object
$hStuff; handle
$bStuff ; binary, true/false
$iStuff ; integer
$nStuff ;number
$g*stuff ; global variable
$c*stuff ; constant

If there is a more complete list, a link would be appreciated. I think there is a name for that syntax after some old school programmer, but for the life of me can't remember.

I used to be really bad at doing that, and still revert to bad syntax when throwing out examples.

I don't know what is a normal prefix for static, I never saw that keyword before perusing this thread.

At first I didn't even get why people put those prefixes in, then once I got it I thought it would slow me down. Now I can't see myself doing anything halfway serious without it.

Edited December 21, 2012 by DicatoroftheUSA

[DicatoroftheUSA]

How to make a variable visible to all functions?

Passing the value through arguments. Though in some cases such as event or callback functions, there may not be an alternative.

But I still prefer using local/passed argument variables, because cause/effect is easier to trace in my opinion.

[BrewManNH]

Notable mention is using prefix to indicate the type of expected variable.

If there is a more complete list, a link would be appreciated.

http://www.autoitscript.com/autoit3/udfs/UDF_Standards.htm

I think there is a name for that syntax after some old school programmer, but for the life of me can't remember.

Are you thinking of Hungarian notation? Probably one of the most confusing ways to name a variable. Edited December 22, 2012 by BrewManNH

[czardas]

How to make a variable visible to all functions?

Yes that can be tricky without using globals. To most functions, I generally pass an array of values stored locally within a main function, or read values when I need them: for example from an ini file. It's not always possible to avoid using global declaration, but I believe it is good practice to avoid them.

Edited December 22, 2012 by czardas

[AZJIO]

Passing the value through arguments.

That is to transfer couple of tens triggers from function to function?

As in this case, pass the State of a checkbox from the Options window?

[AZJIO]

for example from an ini file.

If you suggested to use the register, I would reflect.

INI-file is not professional. Since all the functions will be slow as a turtle, if the intermediary is a hard disk.

[czardas]

The ini file was just an example of reading a value instead of having it declared globally. I generally do something like this:

Instead of this:

Global $gArg1 = True, $gArg2 = False

Func _main()
    _1of2($gArg1)
    _2of2($gArg2)
EndFunc

Func _1of2($vParam)
    ; some algorithm
EndFunc

Func _2of2($vParam)
    ; some algorithm
EndFunc

Try to do something like this:

Func _main()
    Local $aArgs[2] = [True, False]
    _1of2($aArgs[0])
    _2of2($aArgs[1])
EndFunc

Func _1of2($vParam)
    ; some algorithm
EndFunc

Func _2of2($vParam)
    ; some algorithm
EndFunc

This is the simplest example I can think of. Instead of using global, try to use local variables.

Edited December 22, 2012 by czardas

[AZJIO]

If everything was so primitive.

[czardas]

If everything was so primitive.

Basic for clarity. I'm not suggesting it is always possible to avoid using global variables, only that it's generally good practice.

The phrase in English is 'If everything was so simple'. You have the Russian version.

Edited December 22, 2012 by czardas

[AZJIO]

The reason is that you accidentally used a reserved name? Usually I remember names of variables. When doubts I press "Ctrl + F" and "Enter".

$g_stuff ; global variable

As said above.

[czardas]

The reason is that you accidentally used a reserved name?

Yes, I think this is the main reason, especially if someone tries to combine different UDFs which use conflicting global constants. That can get really quite awkward. The fewer globals, the better.

Edited December 22, 2012 by czardas

[TheSaint]

There are many uses of Global variables in most of the included UDFs, definitely not a no-no to the devs. Every XXconstants.au3 file is nothing but global variables. It all depends on what you need the variable for that decides its scope.

Very true, perhaps I should have said, that if you have to use a Global in a UDF or Include, that you damn well better make sure it is uniquely named and extremely unlikely to be used in a script that could use them.

I've never created either, but I have very carefully modified a few, and encountered the perils of Globals in them.

Is there a set standard for this, like using a certain format, combo of characters, underscore etc?

EDIT

I never make changes to the Includes that come with the AutoIt install, certainly never permanently.

It's mostly ones other people have whipped up. If I have to alter an AutoIt original, it is never to one in the Include folder, but to a copy in my script folder, for a one off scenario.

Edited December 22, 2012 by TheSaint