develooper Front page | perl.perl6.language | Postings from May 2005

Re: reduce metaoperator on an empty list

Thread Previous | Thread Next
From:
Rob Kinyon
Date:
May 18, 2005 19:56
Subject:
Re: reduce metaoperator on an empty list
Message ID:
703844205051819554d5d4e2e@mail.gmail.com
On 5/18/05, Stuart Cook <scook0@gmail.com> wrote:
> To summarise what I think everyone is saying, []-reducing an empty
> list yields either:
>
> 1) undef (which may or may not contain an exception), or
> 2) some unit/identity value that is a trait of the operator,
>
> depending on whether or not people think (2) is actually a good idea.

I would think that the Principle of Least Surprise points to (1),
given that the standard explanation of the [+]@x is eval join( '+', @x
) ...

Rob

Thread Previous | Thread Next


nntp.perl.org: Perl Programming lists via nntp and http.
Comments to Ask Bjørn Hansen at ask@perl.org | Group listing | About