nul and non null types

[Mildred Ki'Lya]

Hi,



earlier, we discussed the possibility to specify in the type of a local
(possibly a parameter to a function) if it should be allowed to be null
or not.

I recently found an interesting syntax, but we have to spend a special
character for it (it shouldn't be ambiguous though). It comes from the
vala language: http://www.vala-project.org/doc/vala/types.html#nullabletypes


local : TYPE?
    (local is allowed to be NULL)

local : TYPE
    (local must never be NULL, if it is, it's an error, either
compile-time or run-time)


That was my idea of the moment.

-- 
Mildred Ki'Lya
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