Re: next "big" language?? (disagree)

[ag129@ucs.cam.ac.uk (A. Grant)]

In article <4pj8p7$h9r@goanna.cs.rmit.EDU.AU> rav@goanna.cs.rmit.EDU.AU (++           robin) writes:
>        >euahjn@eua.ericsson.se (Henrik Johansson) writes:
>        >>assertion expression found in other languages like Eiffel (
preconditions,>        >>postconditions, assertions).

>---What is the point of this?
>   A declaration buried somewhere else, and a test.
>   Why not something in clear english, which doesn't need a
>reference to some other part of the program, like:

>   if mod(x, 2) ^= 0 then
>        put ('The value of x is not odd.');

The point of assertions is not to print messages for the 
programmer.  You can use them to allow the compiler to 
optimise safely, provide a contractual interface between 
modules, and for preconditions, postconditions, loop invariants
etc. when proving the correctness of programs.

E.g. the assertion that X is odd could form part of the 
declared interface to a module whose implementation was hidden.