Book in the works by Alexander Stepanov

[Manfred_Nowak]

Andrei Alexandrescu wrote:

> resolves the recent digitalmars.d debate on interface design

1) This seems to be a misinterpretation of the citation.

Whether a specific procedure belongs to the computational basis of a 
type T is a matter of the specification of that type T. This 
specification cannot be inferred from the content of that citation.


2) Applied to the specific problem the framwework of the citation 
only says: 

| iff a type T=List needs a random access operator according to its
| specification, and there is no basis from which such an operator
| can be built more efficiently, then that random access operator,
| probably opIndex, is _allowed_ to be in the computational basis.

It is allowed to be in the computational basis, iff it makes the 
basis more _expressive_.

It is _required_ to be in the computational basis, iff it enables the 
basis to be more efficient.  


3) If an analogy to numbers is allowed, then a procedure of a 
computational basis of a type might be similar to a prime number, and 
a set of procedures might be similar to a set of prime numbers.

Sorrily Stepanov gives no answer for the immidiately rising question 
what the restriction of a finite computational basis implies for 
computational hard/intractable problems.

-manfred   


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If life is going to exist in this Universe, then the one thing it 
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