Re: Fun with C

[Georg Bauhaus <rm.dash-bauhaus@futureapps.de>]

On 4/17/11 9:35 PM, Elias Salom�o Helou Neto wrote:

> Someone has written a line of code without knowing what it does. Is it
> a language problem? Not that C is spectacular, but blaming the
> language here is not fair. Minimally competent C programmers do know
> about such conversions.

OK, that's a claim.  Michael Barr seem to have found results
contradicting it if the "minimum" is what you minimally
find with professional C programmers. In his netrino.com embedded
C quiz, he found that US takers got at D+ on average.
That's a real world, observable minimum, then.

I suggest turning to observable facts and away from
normative ontology for a moment.  Towards justifiable
language design.

Whenever a statistical phenomenon is observed,
many start looking for correlations and hypotheses.
Here, we have errors related to the / operation and
the promotion rules of C's $6.3.1.  Is there a correlation?
Will the correlation between error rates and language
rules  be the same if using another language?
Is that other language intrinsically better or worse, then?

If there is a correlation between the frequency of a number
of programming errors (in this case related to +,-,*,/ etc)
and the way the corresponding part of the programming language
is defined (in this case operand treatment), then I suggest
the following

Hypothesis 1:

A language A is better designed than another B if,
after comparable introduction to the languages,
programmers of an A-group make fewer mistakes than
programmers of a B-group when implementing the same
algorithm.

If so, then competent, informed language *design* will have to
consider expected error rates when defining the language.
Because the definitions affect error rates.

A second perspective:

Definition: The complexity of / (or another language feature) is
the number of concepts that a human mind will have to connect
properly in order to use / (or another language feature) correctly.

Assumption:  Programming is a human activity.
Since programs express human ideas, clear means of expression reflect
programmer intentions better than formally implicit means that
in addition depend on statements outside the language, as is the
case with C's fundamental types.

I suggest, then,

Hypothesis 2:

A language A is better designed than another B if an
understanding and using the language properly is less complex,
that is, in order to express the same algorithm,

(a) it requires thinking about fewer interconnected, possibly
implicit concepts and

(b) depends less on statements outside the language.