Safe Navigation Operator “?.” for D2 ?

[Russel Winder]

On Thu, 2014-02-27 at 20:49 +0000, deadalnix wrote:
> On Thursday, 27 February 2014 at 13:27:14 UTC, Remo wrote:
> >
> > Apparently C# will get it in the next version.
> > http://blogs.msdn.com/b/jerrynixon/archive/2014/02/26/at-last-c-is-getting-sometimes-called-the-safe-navigation-operator.aspx
> >
> > What do you think how well would this work in D2 ?
> 
> Chaining . operation is a code smell to begin with, and having
> everything nullable is dubious as well. This is fixing a problem
> that shouldn't exists to begin with.

>From the responses, this is clearly an emotive issue, but chaining .
operations and using fluent interfaces is only a code smell to those
people who think it is a code smell. Many people think exactly the
opposite and that not using chaining where is can be used is a code
smell.

Groovy has had safe dereferencing for a long time, as have other dynamic
languages, C# is coming very late to this game. Any design decision for
D needs to look wider than the C# debate, theoretical examples and
philosophizing, to actual use in real situations by languages that have
chosen to realize this idea.

My experience from Groovy, which is relatively limited in that I am not
involved in end-client applications only in maintaining and developing
Groovy, GPars and Gant, indicates that it is a very helpful tool,
analogous to the whole Maybe/Option stuff in pure functional languages.

Groovy is now able to probe the issue of whether this operation is as
useful/applicable in a statically compiled context as in a dynamic
context since the @TypeChecked and @CompileStatic AST transforms allow
Groovy to be a static language as Java, Scala, Ceylon, Kotlin are, as
well as being a dynamic language as JRuby, Jython, Clojure are. No
results as yet though as the experiments have not been explicitly tried.
Thus there is no explicit data to reflect on. 
-- 
Russel.
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