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# 1  
Old 03-07-2011
eval
hi all,
Am trying to add some code to a ksh script and i dont understand how an eval function is used :

Code:
_var=$1
    _conceal=$2

    eval _val=\$${_var}

can someone shed some light on what the eval function in the above context means/does ??

thanks.
# 2  
Old 03-07-2011
It's setting _val to the value of the variable whose name is currently in _var


e.g. if _var is PATH is will set _val to contain the value of $PATH

Might be interesting to add:
Code:
echo $_val

to the bottom of this script and then call it with the params HOME testing or _conceal "my value"
Last edited by Chubler_XL; 03-08-2011 at 05:18 PM..
# 3  
Old 03-07-2011
Quote:
Originally Posted by Chubler_XL
It's setting _var to the value of the variable whose name is currently in _var


e.g. if _var is PATH is will update _var to contain the value of $PATH
For the first and last uses of _var in the quoted text, I believe Chubler_XL meant _val Smilie

Cheers,
Alister
This User Gave Thanks to alister For This Post:
Chubler_XL
# 4  
Old 03-08-2011
Thanks Alister,

I read the line
Code:
eval _val=\$${_var}

as
Code:
eval _var=\$${_var}

more than one too, guess I just saw what I expected. I've corrected my original post.
# 5  
Old 03-08-2011
color tags don't work in icode for some reason, just code.
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