no good default issue

[Jack Ammo]

feel free to disregard if this doesn't make sense, but i wonder if the
definitely unassigned / definitely assigned rules coupled with an explicit
opt in default could help the situation.

if we know that a field has not been explicitly assigned, can there be a
quick check if the class opts in to a default factory (a no arg constructor
perhaps?) and then takes the slower path of calling that factory? or maybe
upon accessing a definitely unassigned field, do the check and call the
default factory? i don't know how expensive it would be to keep track of
that, but if the opt in is a no arg constructor then there can be enough
restrictions in place to only allow either throwing an exception or pass
relevant defaults to the full all arg constructor.

and if you're willing to go the default no arg constructor route, than i
also have another idea for array initialization... what if you can define a
default "array initializer" (it can sorta look like a constructor if you
squint your eyes just right) except it takes in an array with definitely
unassigned elements of the value type and must return an array with
definitely assigned elements or throw an exception. and than that class
opts in to a slower path for arrays created with the default value.

just my 2 cents.
-Jack