[julia-users] Re: isnull woes
I think while a Java Null and Nullable Null are different, asking the
question isnull is a similar enough concept to deserve the same
function. The Base/Nullable method is isnull(::Nullable), while the
JavaCall method is isnull(::JavaObject{T}) .. which is the way it should
be, afaics. It's only my wish to write a package that works accross 0.3 and
0.4 that introduces the problem.
On Saturday, 14 March 2015 11:14:58 UTC, Toivo Henningsson wrote:
Do we consider nullness of java objects and nullables to be similar enough
that they should actually be checked with the same predicate? I guess the
two concepts do have a lot of things in common, though methods written to
work with nullables might not be prepared to accept java objects.
[julia-users] Re: isnull woes
You could conditionally use Compat. Something like module Foo export isnull if Base.VERSION v0.4 using Compat import Compat: isnull else import Base: isnull end # new method for isnull end should work. On Friday, March 13, 2015 at 8:54:55 AM UTC-7, Avik Sengupta wrote: So JavaCall has always had an isnull(::JavaObject) method, which is exported. Now that Base has Nullable in v0.4, it also has an isnull(::Nullable) method exported. So far so good. But I want to use Compat for JavaCall, primarily for the Int/int change. Now, Compat also has an isnull(::Nullable) method exported, but that is in the module Compat! So I cant figure out how to write the definition of isnull in JavaCall, that'll work in all versions of Julia. Any help appreciated. Regards - Avik PS Maybe this is another reason why new functionality should NOT be backported, even in compat?
[julia-users] Re: isnull woes
Regarding the PS, just because it possibly causes problems in one edge case is no reason to not make backports available to assist in making code run across multiple versions, to assist in porting, and to keep packages running on stable Julia. The benefits far outweigh the occasional cost, sorry you might have got hit with the cost. Cheers Lex On Saturday, March 14, 2015 at 1:54:55 AM UTC+10, Avik Sengupta wrote: So JavaCall has always had an isnull(::JavaObject) method, which is exported. Now that Base has Nullable in v0.4, it also has an isnull(::Nullable) method exported. So far so good. But I want to use Compat for JavaCall, primarily for the Int/int change. Now, Compat also has an isnull(::Nullable) method exported, but that is in the module Compat! So I cant figure out how to write the definition of isnull in JavaCall, that'll work in all versions of Julia. Any help appreciated. Regards - Avik PS Maybe this is another reason why new functionality should NOT be backported, even in compat?
