Eval() = Evil?

[trids]

I have a string that I want to evaluate, but both the following examples always return @error =1 :

$sEval = "23 >= 20"  ; hoping for a true(-1?) or false value here
$sEval = "23 + 20"   ; expecting 43 here

;but here comes @error = 1 .. 
$ynResult = Eval($sEval)

I can't seem to get an believable answer out of Eval(). What am I doing wrong?

(I'm on AU3 v 3.0.100 with NT4, me)

[Jon]

Eval doesn't execute code like that - it simply gives you the value of a variable.

$test = 1

Eval("test")

[trids]

Thanks for the prompt reply, Jon .. but ..

Ick! Such bad news!

I kind of got the idea that this was what Nutster was talking about when it was first suggested? Though I confess I may have misundserstood!

Would this be a worth suggesting in the Ideas forum? Or is it a bit of a tall order?

(( go on, admit - it can be very useful ))

[MattNis]

originally I thought eval would do the same thing as you did, Trids.

something like...

$val = active

eval("WinWait" & $val(window name, text))

[CyberSlug]

Trids, you could try a workaround like this:

Write out the statement to a secondary script which you run to obtain the result. This example uses the clipboard to transfer the data.

$sEval = "23 >= 20"

$bak = ClipGet()

FileDelete (@TempDir & "\foo.au3")
FileWriteLine (@TempDir & "\foo.au3", "$x =" & $sEval)
FileWriteLine (@TempDir & "\foo.au3", "ClipPut($x)" )

RunWait("C:\Program Files\AutoIt3\AutoIt3.exe " & '"foo.au3"', @TempDir)
$ynResult = ClipGet()
ClipPut($bak)

MsgBox(4096,"", $ynResult)

P.S. True is any non-zero number (typically 1), and False is zero.

Edited March 25, 2004 by CyberSlug

[Nutster]

Sorry to mislead you guys, but that was what I was looking at doing. Jon implemented the much simpler version that just looks up variable values. You could try:

$sEval = (23 >= 20) ; hoping for a true(-1?) or false value here
MsgBox(0,"Testing", $sEval); Actual gives 1 (for true)
$sEval = (23 + 20)  ; expecting 43 here

;but here comes @error = 1 ..
$ynResult = Eval($sEval)

I would still like to do something like this, but I have to see how to prevent the calling of keywords, like Dim, While, If, and functions with side-effects, like FileRecycle, WinWait and ShutDown.