Re: In precision typing we trust

["Björn Persson" <Bjorn@xn--rombobjrn-67a.se>]

Paul Rubin wrote:
> Python is reasonably reliable in the
> sense that programs with errors will probably crash instead of going off
> into the weeds.  The saying is that correct code is great, code that
> crashes could use improvement, but incorrect code that keeps running and
> delivering wrong results is a disaster.

Then let me tell you about a disaster.

I once worked with a team of testers who wrote their testcases in
Python. Each testcase was supposed to return True or False to report
whether the test had succeeded or failed. Some testcases returned the
string "true" or "false" instead. When an if statement is applied to a
string in Python, "" is considered false but "false" is considered true.
Thus the test framework kept running and reported the failing test as
successful. The testers didn't notice. They didn't have tests to test
their testcases.

Whether that's reasonably reliable depends on one's opinion on what's
reasonable, I suppose.

As you guys are arguing – or rather talking past each other – about
Python in comp.lang.ada, can I assume that you all know what an Ada
compiler would do with such code?

Björn Persson