[julia-users] How to make generic constructors with no arguments work?

[SZubik]

Hi,

For some reason I can't figure out the following, maybe someone encountered 
this before.
For example I have the following type

type A{T}
  item::Nullable{T}
end

and 

A{Int64}(2) 

returns A{Int64}(Nullable{2}) as expected.

However I want to introduce a constructor with no parameters (so by default 
item is null):

type A{T}
  item::Nullable{T}
  function A{T}()
    new{T}(Nullable{T}())
  end
end

And I get

WARNING: static parameter T does not occur in signature for call at line 4
The method will not be callable.


As expected, I get some error when try to call it:

A{Int64}()

Error:

LoadError: MethodError: `convert` has no method matching 
convert(::Type{A{Int64}})
This may have arisen from a call to the constructor A{Int64}(...),
since type constructors fall back to convert methods.


If someone could help me make sense out of this, it would be much appreciated :)

Thanks