[comp.lang.ada] Strong vs. Weak Typing

murali@tut.cis.ohio-state.edu (S Muralidharan) (01/08/90)

In article 2562, eberard@ajpo.sei.cmu.edu (Edward Berard) writes:

>responses. I would be interested in getting your reaction to the
>following quotes from one of respondees:

>>>         object-oriented programming. Smalltalk has, in effect, no
>>>         types, but there are typed extensions to Smalltalk, e.g.,
>>
>> Again, CL and Smalltalk have *run-time* types - restrictions on
>> the use of *objects* during program *execution*.  Languages such
>> as Ada have *compile-time* types - restrictions on the use of
>> *identifiers* during program *compilation.*

>Are there any references documenting the benefits of strong vs. weak
>typing? What are your reactions to the definitions given?

This is really an interesting issue.  I have more fundamental questions.
What are types?  Why do we need types in programming languages? 
"Type" seems to have several different meanings (see Danforth, S., and
Tomlinson, C., "Type Theories and Object-Oriented Programming," ACM
Computing Surveys 20, 1, March 1988, pp. 29-72), and not even
apprently rigorous and apparently formal ones do much to illuminate
the concept, only to make it seem mysterious. 

Cheers,

Murali