What happens if find_student() doesn't find the given student? Undef is returned, which the code then attempts to use as a student object by invoking the display method. You're going to have to check the return value before doing this.

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

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