The problem is, as you appear to have noticed, down to the order of calling and declaring the function.

If the declaration precedes any call, perl already knows that print_argu arg,...; is a call to a sub, whereas if the order is reversed i.e. the call precedes the declaration, perl needs a hint as to what sort of symbol print_argu represents. In this case, the hint can be either...

i.e. either of the following will work 
print_argu("Hello function!\n");
sub print_argu{
    print "@_\n";
}

[download]
or 
sub print_argu;
print_argu "Hello function!\n";
sub print_argu{
    print "@_\n";
}

[download]

That being said, it is recommended, in PBP, that the parens are omitted only for calls to builtins.

A user level that continues to overstate my experience :-))

In reply to Re: function calling by Bloodnok
in thread function calling by vinoth.ree

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