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digitalmars.D - Re: Null references redux

Walter Bright Wrote:

 Denis Koroskin wrote:
 One more:
 T foo(bool someCondition)
     T? t;
     if (someCondition) t = someInitializer();
     // ...
     if (t.isNull) { // not initialized yet
         // ...
     return enforce(t); // throws if t is not initialized yet, because 
 foo *must* return a valid value by a contract

It seems to me you've got null references there anyway? What would you do about: T[] a; a[i] = foo(); where you want to have unused slots be null (or empty, or nothing)?

Your example segfaults. A is null. If T is const or immutable, special care is also required.
Sep 26 2009