eval return value 2

[vbkris]

i have a function:
function ASD()
{
return "AD";
}

another function:
function asd1()
{
$vl=eval("AD();&quot
echo $vl;
}

$vl is empty(even though a value is returned)... why?

is there a workaround?

Known is handfull, Unknown is worldfull

 

[DRJ478]

Is it just a typo or did you mean to call the function AD() instead of ASD()?

 

[vbkris]

oops its a typo:
i want to call ASD()
$vl=eval("ASD();&quot


Known is handfull, Unknown is worldfull

 

[danielhozac]

Your eval should read
[tt]$vl = eval("return ASD();"[/tt]

//Daniel

 

[DRJ478]

Your string that is evaluated does not contain a return reference. The function which you defined does - but that oly works inside the function.

What you need to do is to return the result of ASD():

$vl = eval("return AD();");

The internal return only returns the result of the function and has no bearing for the eval() function.

 

[vbkris]

Ur right...

but can u tell me why i need another return in the eval?

Known is handfull, Unknown is worldfull

 

[danielhozac]

Heh, looks like DRJ478 just did.

//Daniel

 

[vbkris]

oops i couldnt read DRJ's post...

i have read it only now...

DRJ:
>>but that only works inside the function

what does this mean?

Known is handfull, Unknown is worldfull

 

[DRJ478]

Ok,

You asked for it. Here is a more verbose answer.

Functions return values to a caller. That's the nature of (most) functions, including your ASD(). When you call ASD() the function returns the value you assigned inside the function.
Just doing eval("ASD()" is like a simple assignment. You could think about it as

eval("$myvalue = ASD();");

Now you can see that the evaluated code actually does not return anything, because it is not told to, it just executes the function.

In order to return the result of the function as the result of the eval() function the return statement must be in the evaluated code.

Visualize eval as:

function eval(){
  # do something like
  $myVar = ASD();
  return $theResult;
}

 

[vbkris]

yup..

i got it...

so eval() doesnt return anything (ur function eval() expalained it all....)

thanks...

Known is handfull, Unknown is worldfull