[Python-ideas] Pre-conditions and post-conditions

[Steven D'Aprano]

On Mon, Aug 27, 2018 at 09:24:20AM +0100, Ivan Levkivskyi wrote:
> TBH, I think one of the main points of design by contract is that contracts
> are verified statically.

No, that's not correct. Contracts may be verified statically if the 
compiler is able to do so, but they are considered runtime checks. 
Static checks are an optimization.

For example, the Eiffel docs describe one possible contract as "the 
graph contains no cycle" and can contain function calls.

https://www.eiffel.org/doc/eiffel/ET-_Design_by_Contract_%28tm%29%2C_Assertions_and_Exceptions



-- 
Steven