Sams Teach Yourself Perl in 21 Days, Second Edition

A Note About Using Functions

Now that you've learned about the print and chomp functions, as well as had a glimpse of other functions such as int and sprintf, this is a good time to go over how function calls work. If you've been paying careful attention, you might have noticed that I've been calling the print function like this:

print "Hello, World!\n";

I've also been calling chomp and printf like this:

chomp($input = <STDIN>);
printf("Average (mean): %.2f", $avg);

One form has parentheses around the arguments to the function, the other form doesn't. Which is correct? The answer is both. Parentheses around the arguments to a function are optional; as long as Perl can figure out what your arguments are, either form works just fine.

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