The Existential Operator

Andrea Giammarchi andrea.giammarchi at
Thu May 22 11:04:37 PDT 2014

Still haven't seen a convincing example but if generally everybody thinks
is a must have I'll look quietly aside.

Take care

On Thu, May 22, 2014 at 10:17 AM, Claude Pache <claude.pache at>wrote:

> Le 21 mai 2014 à 01:30, Andrea Giammarchi <andrea.giammarchi at> a
> écrit :
> >
> > FWIW I think having silent failures all over is not desirable so I'd
> like to know what's the concrete claimed need for this, if that's possible.
> (I've only read there's a need but I don't find the rationale)
> The point of the Existential Operator in general, and of the details of
> its semantics in particular, is not to fail silently (although it can be
> abused for that), but to have a compact syntax for concrete cases where you
> must be prepared to receive either null/undefined or an object (as it
> happens when working with the DOM), and want to yield another value using a
> definite algorithm (accessing properties, invoking methods). Or do you
> think to a precise detail of the semantics of the Existential Operator,
> where silent failures are encouraged?
> —Claude
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