On 12/27/2017 8:38 AM, Laeeth Isharc wrote:
On Wednesday, 27 December 2017 at 07:44:30 UTC, Walter Bright wrote:
On 12/26/2017 4:18 AM, Russel Winder wrote:
All of which brings us full circle: when it comes to programming
languages and software development, it is all about advocacy,
prejudice, and belief, there is very, very little science happening –
and most of the science that is happening is in the psychology of
programming, about which most developers of programming languages know
nothing.
If you're hinting that I know nothing about the topic, you're mistaken :-)
A fair amount of D's design is based on psychology.
I'd love to hear more about this sometime.
One fun example is our quest to find the right keyword for read only data. A
long list of words were examined, like readonly, invariant, etc. Some had
various baggage connotations, some weren't clear what they meant.
We found ourselves constantly saying things like: "readonly means immutable",
"invariant means immutable", etc. Finally we got hit with a clue-by-four -
everyone understood what "immutable" meant, so why not just use "immutable"?
Pure psychology, and nothing to do with computer science.
---
Another is it is known that people have cognitive problems with negation. It
often just does not register in the mind. This is why version statements in D do
not have negation. It more or less forces one to think of using positive version
identifiers:
version (hasFeature) { ... }
as opposed to:
version (!hasFeature) { ... }
or even worse (yes I've seen it):
version (!doesNotHaveFeature) { ... } // :-(
In order to do negation, one must resort to:
version (hasFeature) { } else { ... }
Having converted a lot of C code to D and dealing with things like:
#if !__OSX__
... call X ...
having to redesign the case to use positive features:
version (hasX)
... call X ...
makes the code a lot more readable. It's worth it.
The psychological cognitive issues around negation are known, but I rarely see
deliberate efforts by programmers to deal with that issue. D kinda forces it,
and I get resistance to it, but it is worthwhile to push it because the results
are worth it.
