Not sure what you're trying to point out.  Class methods don't need an object instance to be called upon.

If you look at the implementation of MIME::Lite::send(), 

sub send {
    my $self = shift;
    my $meth = shift;

    if ( ref($self) ) {    ### instance method:
        my ( $method, @args );
        if (@_) {          ### args; use them just this once
            $method = 'send_by_' . $meth;
            @args   = @_;
        } else {           ### no args; use defaults
            $method = "send_by_$Sender";
            @args   = @{ $SenderArgs{$Sender} || [] };
        }
        $self->verify_data if $AUTO_VERIFY;    ### prevents missing pa
+rts!
        Carp::croak "Unknown send method '$meth'" unless $self->can($m
+ethod);
        return $self->$method(@args);
    } else {                                   ### class method:
        if (@_) {
            my @old = ( $Sender, @{ $SenderArgs{$Sender} } );
            $Sender              = $meth;
            $SenderArgs{$Sender} = [@_];       ### remaining args
            return @old;
        } else {
            Carp::croak "class method send must have HOW... arguments\
+n";
        }
    }
}

[download]

you'll see that in the else branch (### class method), the send method to be set as default is stored in some global variable $Sender together with the arguments in $SenderArgs{$Sender}.

Those values are then being used when send() is called as an instance method. What makes the program croak is that $self->can($method) is failing, because - apparently - there is no 'send_by_smtp' method in the OP's case.  I can't tell why, however — my version of MIME::Lite does have such a method.

In reply to Re^4: Getting Error "Unknown send method" when sending mail using MIME::Lite?? by almut
in thread Getting Error "Unknown send method" when sending mail using MIME::Lite?? by Sachin

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