[Closed] How Can I do 2 Operations in a While Condition?

[Zohar]

Hi

I need to do 2 operations in a While's Condition.

The 2 operations are:

1) Setting a Variable

2) Conditioning, according to the Content of the Variable that was just assigned

I need something like this:

While ( $Data=SomeFunctionForGettingTheData() ) = ""
     Operations
Wend

In many programming Languages,

the While condition that I just wrote, will do 2 operations:

1) It will do the assinment $Data=SomeFunctionForGettingTheData()

2) It will check the properly check if the value assigned, equals "",

And the reason it will do it, because an assignment's return value, is the value that was assigned.

(so like, the value of a codepiece like that $V=5, will be 5)

How can I make the same in AutoIt?

Thank you

Edited August 10, 2012 by Zohar

[Melba23]

Zohar,

I would use a Do...Until loop like this:

Global $sData

Do
    $sData = InputBox("Data Input", "Input here")
Until $sData <> ""

MsgBox(0, "Data Assigned", $sData)

That way you both assign and check the value in the loop.

M23

[Zohar]

Hi Melba23

Thank you,

The only problem is that we have the Operations part.

I need both the Assignment and the Condition to be checked before the Operations block is performed.

What can we do in this case?

I am ooking for a way to write the While's Condition, like in C++,

Where you can write an Assignment to a variable,

and that assignment's value, will also be the value of the whole clause..

Is it somehow possible?

Edited August 7, 2012 by Zohar

[Melba23]

Zohar,

This perhaps:

Global $sData

HotKeySet("{ESC}", "On_Exit")

While 1

    ; Assign and check
    Do
        $sData = InputBox("Data Input", "Input here")
    Until $sData <> ""

    ; Operations
    MsgBox(0, "Data Assigned", $sData)

WEnd

Func On_Exit()
    Exit
EndFunc

But it is difficult to be helpful when I have so little idea of what exactly you are trying to do. There might well be another method more suited but without a better explanation it is impossible to say.

M23

[Zohar]

Right now, my workaround is this:

Local $Data

While True
    $Data =SomeFunctionForGettingTheData()
    If $Data<>"" Then ExitLoop

    ;Operations
    Sleep(1000)
WEnd

However,

If I could have the Assignment and the Condition in the While's Condition clause,

the block could be like this:

While ($Data =SomeFunctionForGettingTheData()) = ""
    Beep(1000,10)
    Sleep(1000)
WEnd

If only an Assignment in AutoIt, returned the Value that was assigned, the whole problem would've been solved..

Regarding your question,

since this problem occured to me in many places,

then there's not just 1 scenario - it's a basic coding problem, it has nothing to do with what you try to achieve in your program..

Edited August 7, 2012 by Zohar

[Melba23]

Zohar,

If I could have the Assignment and the Condition in the While's Condition clause

But I do not believe you can. And all you would achieve is more complicated, but slightly shorter, code - why not KISS?

M23

[Zohar]

OK then.

Thank you Melba..

[MvGulik]

I personally would go with:

...
$Data = SomeFunctionForGettingTheData() ;; first/initiation.
While $Data = ""
    ;Operations
    Sleep(1000)
    $Data = SomeFunctionForGettingTheData() ;; next/continuation
WEnd
...

Although, I figure this is also possible.

...
Dim $Data
While IsEmptyString($Data, SomeFunctionForGettingTheData())
    ;Operations
    Sleep(1000)
WEnd
...
Func IsEmptyString(ByRef $Data_out, $Data_in)
    $Data_out = $Data_in
    Return ($Data_out = "")
EndFunc

[Zohar]

I personally would go with:

...
$Data = SomeFunctionForGettingTheData() ;; first/initiation.
While $Data = ""
;Operations
Sleep(1000)
$Data = SomeFunctionForGettingTheData() ;; next/continuation
WEnd
...

The only problem with it, is that you repeat the $Data = SomeFunctionForGettingTheData() line.

Although, I figure this is also possible.

...
Dim $Data
While IsEmptyString($Data, SomeFunctionForGettingTheData())
;Operations
Sleep(1000)
WEnd
...
Func IsEmptyString(ByRef $Data_out, $Data_in)
$Data_out = $Data_in
Return ($Data_out = "")
EndFunc

This one is interesting

Thanks

[ajag]

Zohar,

The only problem with it, is that you repeat the $Data = SomeFunctionForGettingTheData() line.

See your "I need something like this:" example of your first post:

While ( $Data=SomeFunctionForGettingTheData() ) = ""
Operations
Wend

Since the condition has to be checked every loop count the "$Data=SomeFunctionForGettingTheData()" part in the while condition will be repeated every loop count also. So it doesn't matter if it is done in the while-condition or within the loop.

Or did I missunderstand you?

A-Jay

Edited August 8, 2012 by ajag

[Zohar]

The problem is not that the "$Data=SomeFunctionForGettingTheData()" will run every iteration - it needs to run every iteration.

The problem is in the fact that the discussed idea, contains code duplication, which should be avoided, for many reasons.

[BrewManNH]

The problem is in the fact that the discussed idea, contains code duplication, which should be avoided, for many reasons.

No it shouldn't, if you need to check it before the While loop, check it before the While loop. There's nothing wrong with that scenario. It would be the same if you were using a timer in a While loop, you would set the TimerInit() before the While loop, and then reset it with the same line inside the loop.

[Zohar]

BrewManNH,

I completely disagere with you on this one.

But you can code however way you prefer.

I code the way I prefer.

If AutoIt made Assignment Statements return the value of what was just assigned (like it happens in all other programming langauges),

then the problem would have not existed.

But from the comments here, it seems that there's no way to solve it.

So I used the workaround I mentioned.

Edited August 10, 2012 by Zohar

[BrewManNH]

If AutoIt made Assignment Statements return the value of what was just assigned (like it happens in all other programming langauges),

then the problem would have not existed.

Not ALL other programming languages, Python for instance doesn't return a value on an assignment. But that's neither here nor there, AutoIt doesn't, and workarounds can be done as you say.

[Zohar]

OK