I have the first version of Modern Perl to hand. In page 9 of the PDF (numbered page ii - the first page of the preface) it says this:

Unless otherwise mentioned, code snippets always assume the basic skeleton of a program: 
#!/usr/bin/perl

use Modern::Perl;

# example code here
...

[download]

but you have not done this so you encounter the error reported.

In reply to Re: Modern Perl Book "Paquito" Example Question by hippo
in thread Modern Perl Book "Paquito" Example Question by Ayber

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