Carp::Assert: "assert(...) if DEBUG;"i.e. by the fact that you have to append "if DEBUG" to an assertion in order to get it disabled in production.
Now, I have flipped.
I often want assertions enabled in production code. At least cheap assertions. In fact, I might go so far as to say "assertions should be enabled in production code by default, unless you explicitly say not to".
In which case, the Perl Carp::Assert syntax is not totally unreasonable.
I might prefer the Pythonish
if DEBUG: assert(...)
so that you can see the "if DEBUG" right up front.
But then again, Python's assert is disabled when you run Python "optimized" via python -O.
I was somewhat flabbergasted when I encountered Python style guides that recommended not using asserts, or specifically not using asserts inside library functions. (Can't find a reference right now, so perhaps this is rare advice.)
Reason: since Python assert is disabled when you run optimized -O (which is common in some worlds), and since libraries cannot be sure that somebody competent is calling them, libraries should do
if !valid(parameter): raise someExceptionrather than
assert valid(parameter)This advice is accurate, but unfortunate. I always prefer concise code, and "assert" is more concise than "if...raise". And probably less fragile, since exception hierarchies have a habit of changing.
So I can't blame Python, but I can still regret it.
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