(j3.2006) Parent component of extension of abstract type

Cohen Malcolm malcolm
Thu Nov 12 19:56:05 EST 2015

>Maybe we should allow to instantiate nonpolymorphic objects of abstract

Not being able to instantiate objects is a fundamental point of abstract 
types.  If you can instantiate them, the whole abstract edifice falls to the 
ground - there can be no compiler protection against mistakes (that being 
the only reason it was worth adding abstract types in the first place).  If 
abstract were limited to a gentle reminder that you're supposed to do 
something with the deferred type-bound procedures when extending, it would 
not have been anywhere near valuable enough to be an actual language 

If you need to instantiate them, then just don't make it abstract.  It's as 
simple as that.

........................Malcolm Cohen, Nihon NAG, Tokyo. 

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