Your error happens because</c> 

find_student($reg)

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returns undef, which most likely means that no student matching $reg was found. Consider checking the values you have in your database and whether/how a student can be found given $reg.

In reply to Re: How can one define value to call method "display" at line 45? by Corion
in thread How can one define value to call method "display" at line 45? by supriyoch_2008

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