The defined Function : defined « System Functions « Perl

1. Perl
2. System Functions
3. defined

The defined Function

      

#If a scalar has neither a valid string nor a valid numeric value, it is undefined. 
#The defined function checks for the validity of a variable's value. 
#defined Function returns 1 if the variable has a value and null if it does not. 
#defined Function also checks the validity of arrays, subroutines, and null strings.


$name="A";
print "OK \n" if defined $name;

   
    
    
    
    
    
  

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