Why no overloaded functions in perl?

Because you can inspect the argument count, return context, and object types all by yourself. In Perl, the number of arguments is trivially available to a function via the scalar sense of @_, the return context via wantarray(), and the types of the arguments via ref() if they’re references and simple pattern matching like /^\d+$/ otherwise. In languages like C++ where you can’t do this, you simply must resort to overloading of functions.

What read() returns at end of file in perl?

0. A defined (but false) 0 value is the proper indication of the end of file for read() and sysread().

How to sort hash by value in perl.

#!/usr/bin/perl -w
sub Ascending { $grades{$a} cmp $grades{$b}; }
sub Descending { $grades{$b} cmp $grades{$a}; }
%grades = (
student1 => 90,
student2 => 75,
student3 => 96,
student4 => 55,
student5 => 76,
);

foreach $key (sort Descending (keys(%grades))) {
print "$key : $grades{$key}\n";
}

// Using the Ascending subroutine will print the values in ascending order.

How to read file into hash array in perl?

open(IN, “<name_file”) or die “Couldn’t open file for processing: $!”;
while () {
chomp;
$hash_table{$_} = 0;
}
close IN;
print “$_ = $hash_table{$_}\n” foreach keys %hash_table;

How to find length of an array in perl?

This will give you the length of an array :
$@array

Value returned by return statement in perl?

The undefined value in scalar context, and the empty list value () in list context. This way functions that wish to return failure can just use a simple return without worrying about the context in which they were called.
 

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