Love it
Gianluca Sartori -- Cell. +39 388 1026822 On Wed, 11 Dec 2024 at 02:33, Paul King <pa...@asert.com.au> wrote: > I created this pull request which clarifies things somewhat: > > https://github.com/apache/groovy/pull/2133 > > But feel free to create an alternative if you think it can be improved > further. > > Cheers, Paul. > > On Wed, Dec 11, 2024 at 12:58 AM Milles, Eric (TR Technology) > <eric.mil...@thomsonreuters.com> wrote: > > > > > If you think of def and var as an alias of Object, you will understand > in an instant. > > > > I too think this line should be replaced. There are circumstances where > def only means "define" and is not a type placeholder. > > > > multi-variable declaration: def (a, int b, char c) = [0,1,'2'] // def is > not synonymous with Object > > > > I would argue that def for method/function/procidure declaration also > means "define" > > > > > > ________________________________ > > From: o...@ocs.cz <o...@ocs.cz> > > Sent: Tuesday, December 10, 2024 8:49 AM > > To: Groovy_Developers <dev@groovy.apache.org> > > Cc: Paul King <pa...@asert.com.au>; MG <mg...@arscreat.com> > > Subject: Re: [EXT] Using `var` as method return type placeholder > > > > Ah, I though we are discussing the real usage/support, not just the > documentation (which of course can be always improved). > > > > Most probably the proper solution would be change the documentation to > something more-or-less like > > > > === > > [def explained without mentioning var] Note that for a seamless > compatibility with a Java legacy code, you can also use var, which can be > placed where Java allows it (typically variable declarations) and where > applicable, it is fully equivalent to def. > > === > > > > Myself, I would also add something like > > > > === > > Although var does work and will work in future all right, when (if ever) > the code is “groovyfied” by removing semicolons, replacing for(:) by for/in > etc., we also recommend to replace vars by defs for consistence (there is > no functional difference though; if you like var personally, feel free to > stick with it, just like you can freely stick with semicolons). > > === > > > > Incidentally, myself, I don't like the “Object alias” part. To me it > seems rather misleading. Frankly I don't know how it currently works (and > what changes, if any, are presumed for future), but in my personal opinion > there's a subtle but important difference: def is just about anything (and > should support type inference far as reasonably possible). Object is an > instance of the Object class (and whether it should infer types even if > possible or not is highly arguable). Nevertheless this path leads to a need > to support something like ObjC __kindof, which Groovy (far as I know) > currently has not, along with better dynamic typechecking etc., and would > open another big can of worms. > > > > To me, nothing of this seems too important though (and had I understood > we are debating docs only, I would not write my previous message quoted > below). Even if the documentation is imperfect (any documentation always > is), it gives a good overall idea how things work; the fine details can be > easily learnt later. > > > > Thanks and all the best, > > OC > > > > On 10. 12. 2024, at 15:21, Gianluca Sartori <g.sart...@gmail.com> wrote: > > > > I might be wrong and I might have misunderstood something of importance, > but it seems to me there is one (and only one) very specific need to use > var: ensuring a code copy/pasted from Java works (with as little number of > problems as reasonably possible). > > > > > > This is what I understood as well reading the docs, but it looks like > `var` is starting to become a full part of the Groovy syntax because it has > been documented along with `def` as equal to `def` (but only for variable > definitions). > > > > > > I would like to use `var` as a return type placeholder meaning "this > method returns a variable" > > > > > > What does it mean? Far as I know (but of course, my knowledge is > limited), there's no var-ref type in Java (nor Groovy), and thus no method > can return a variable. Have I missed something of importance again? > > > > > > You have missed that part in the docs where it says: > > > > > If you think of def and var as an alias of Object, you will understand > in an instant. > > > > So if `var` is an alias for `Object` one should be able to use it as a > type placeholder in method return types as well, but that's not the case > > > > > > > > >
