It's ensuring that shift is being evaluated as a function call and not as a literal string. You don't want 'shift' to be seen as a class name, you want it to be evaluated as a function call, and its return value to be used as the class name or object reference.

Examples: 

my $object = Classname->new();  # Classname is seen as a class name
                                # and new() is a method of Classname.

my $gotten = +subname->new();   # Here subname had better return 
                                # either a valid class name or an 
                                # object capable of having new() 
                                # called as an object method.

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Dave

In reply to Re: What is the + in +shift doing here? by davido
in thread What is the + in +shift doing here? by tphyahoo

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