ISO Studies of underscores vs MixedCase in Ada or C++

[Andy Glew]

I am in search of any rigourous,
scientific, academic or industrial studies
comparing naming conventions in
C++ or similar languages such as
Ada:

Specifically, are names formed with
underscores more or less readable
than names formed with MixedCase
StudlyCaps camelCase?

....and similarly, any measurements
of programmer productivity, bug rate,
etc.; although IMHO readability matters
most.
* Religion - NOT?!

I understand that this is a religious issue
for many programmers, an issue of programming style.
I am not interested in a religious war.
I obviously have my own opinion, but I am
open to scientific evidence.
* Ada Studies?

I thought that I had seen studies like
this in some of the early design documents
for Ada, but I have not been able to find
such references on the web. Which is not
entirely surprising, since Ada was designed
prior to the web.

The Ada 83 and 95 Quality Guidelines recommend
underscores to improve readability, but provide
no source justifying this statement.
* What such studies might look like

Simple readability and recall:
- present a test subject with
a list of compound words
formed with underscoresand mixed case
- remove the list, and ask test subject
to write it
- score on accuracy

Program debugging
- present programs that are otherwise identical,
differing only in their use of underscores/MixedCase
to test subject programmers (e.g. a CS class)
- program has a known bug
- ask test subjects to find bug
- score on accuracy locating bug

Cruel TA study:
- Two sections of a CS class
- Enforce programming standards,
underscores vs MixedCase
- Pose a programming problem
- Score according to success
completing assignment

Empirical:
- Given version control databases
of large programs, some written in underscore
style, others in MixedCase
- Total bug rates normalized by LOC, name count, etc.
- OR: count only bugs that can be attributed
(after inspection of checkins) to misnamed variables

For that matter, I would be interested in any surveys
folks may have done that count projects and their
coding standards, possibly weighted
- open source (e.g. sourceforge)
- industrial
- textbooks, weighted by sales
- websites of coding standards, weighted by Google score...
Although this is less convincing than a rigorous study.
* Explanation of Newsgroups Chosen

I hope it is obvious why I have chosen these
newsgroups to post this search to:

comp.software-eng, comp.programmin g,
- an issue of software engineering
comp.lang.c++,
- the language I am most interested in
comp.lang.ada
- because I vaguely recall historical work

[Peter Ammon]

Wes Groleau wrote:

Peter Ammon wrote:

Agreed! I wish that more languages allowed hyphen use in identifiers.
Dylan is the only one I can think of off the top of my head.

Does Dylan prevent having variables named Max,
Max-Iterations, & Iterations in the same scope?

No. Whitespace is more important in Dylan than in a language like C.

Max-Iterations <-- variable name
Max - Iterations <-- Max minus Iterations

Other strange characters can appear in Dylan variable names. This
allows for some nice naming conventions without the nastiness of
something like Hungarian Notation. See
http://www.gwydiondylan.org/gdref/tu...nventions.html

-Peter

[Steve]

If you happen to be use GNAT (GNU Ada), the compiler does do some degree of
spell checking.

gcc -c dointxor.adb
dointxor.adb:30 :28: "b_valu" is undefined
dointxor.adb:30 :28: possible misspelling of "b_value"
gnatmake: "dointxor.a db" compilation error

If you use the GPS for programming Ada, you'll get a little wrench icon next
to the error in the output window. If you click on the wrench it corrects
the spelling error.

If you're really interested in having comments spell checked, the folks at
ACT (Ada Core Techologies) would probably add the feature for a fee.

Steve
(The Duck)
"Leif Roar Moldskred" <rm******@onlin e.no> wrote in message
news:86******** *******@huldreh eim.huldreskog. no...
[snip]

This touches on one of my pet annoyances with development tools today:
no way to easily spell-check your code. In my opinion, a development
environment should at the very _least_ let you easily spell-check all
the text in comments, and preferably the individual words in variable
and function names (whether the words are separated by mixed case,
hyphens or underscores.)

Unfortunately, nobody else seems to mind. *sighs* Oh well,
spell-checkers are overrated anyway.

--
Leif Roar Moldskred

[Matt Gregory]

James Dow Allen wrote:

(I usually rewind a file with "lseek(fd, 0L, 0)" because I can't
remember if 0 is SEEKSET or SEEK_SET.)

The Vim editor is cool for things like this because you can add your
own words to the syntax highlighting. I write Windows programs and
I have over a hundred typedef's and constants in my word list.
Actually, Vim's C syntax file comes with the standard C constants
and typedef's highlighted.

[Matt Gregory]

Peter Ammon wrote:

Programmer Dude wrote:

Or my preference if the tool allows

classmethod :
access-specifier
method-type-specifier
method-return-type-specifier
method-declaration
method-body

(In proportional fonts, hyphens are usually skinnier than
underscores and (to my eye) make the text more readable.
It's not as noticable with monospace fonts, but I think the
lower example looks better (read: more readable :-).)

Agreed! I wish that more languages allowed hyphen use in identifiers.
Dylan is the only one I can think of off the top of my head.

Lisp and Scheme.

[Leif Roar Moldskred]

"Steve" <no************ *@comcast.net> writes:

If you happen to be use GNAT (GNU Ada), the compiler does do some degree of
spell checking.

gcc -c dointxor.adb
dointxor.adb:30 :28: "b_valu" is undefined
dointxor.adb:30 :28: possible misspelling of "b_value"
gnatmake: "dointxor.a db" compilation error

That's not really spell-checking though - it doesn't check "b_value" to see
if "value" is a proper word in English.

--
Leif Roar Moldskred

[Leif Roar Moldskred]

"Kevin Morenski" <[e-mail] center.net> writes:

Let's say you had a variable named "tHTa," for example. With respect to
your concept, this would be a misspelling of the word "that." Now, a lot of
programmers--myself included--use letters to represent certain things in
variable names. tHTa could mean "type HTa" or anything else a programmer
could think of. How could a program possibly differentiate between
conventions in the naming of variables?

In the same way that spell-checkers for ordinary text today handles names and
other words that are correct, but not in the dictionary: When detecting the
unknown word the first time, ask the user what to do with it - whether to
correct it, accept this instance, accept all instances in this document or
add it to your private dictionary. (For a spell-checking of source-code we'd
probably also want the option "accept all instances with this case.")

This really isn't any different from the same problem in regular text,
except that your programming convention might cause a lot of unknown
words to appear. If that's a major headache, just don't spell-check.

--
Leif Roar Moldskred

[Martin Dowie]

"Matt Gregory" <bl************ ****@earthlink. net> wrote in message
news:BPvfb.2044 5

Agreed! I wish that more languages allowed hyphen use in identifiers.
Dylan is the only one I can think of off the top of my head.

Lisp and Scheme.

COBOL

[Jakob Bieling]

"Leif Roar Moldskred" <rm******@onlin e.no> wrote in message
news:86******** ****@huldreheim .huldreskog.no. ..

"Steve" <no************ *@comcast.net> writes:

If you happen to be use GNAT (GNU Ada), the compiler does do some degree of spell checking.

gcc -c dointxor.adb
dointxor.adb:30 :28: "b_valu" is undefined
dointxor.adb:30 :28: possible misspelling of "b_value"
gnatmake: "dointxor.a db" compilation error
That's not really spell-checking though - it doesn't check "b_value" to

see if "value" is a proper word in English.

But it is that kind of word-matching I would personally like to see in
more compilers (specifically C++ compilers).

I do agree with Kevin Morenski (news:3f******* *@nntp2.nac.net ) that a
real spell-checker for source code is not practicable. You said that the
spell-checker would just have to ask you whether to ignore it or how else to
proceed. Have you thought about how annoying 100s or even 1000s of those
messages boxes, asking how to proceed, will be when compiling already
existing source with this spell-checker?

regards
--
jb

(replace y with x if you want to reply by e-mail)

[Corey Murtagh]

Martin Dowie wrote:

"Matt Gregory" <bl************ ****@earthlink. net> wrote in message
news:BPvfb.2044 5

Agreed! I wish that more languages allowed hyphen use in identifiers.
Dylan is the only one I can think of off the top of my head.

Lisp and Scheme.

COBOL

Isn't there a variation of Godwin's Law covering COBOL? :>

--
Corey Murtagh
The Electric Monk
"Quidquid latine dictum sit, altum viditur!"

[CBFalconer]

Matt Gregory wrote:

Peter Ammon wrote:

Programmer Dude wrote:
.... snip ...

(In proportional fonts, hyphens are usually skinnier than
underscores and (to my eye) make the text more readable.
It's not as noticable with monospace fonts, but I think the
lower example looks better (read: more readable :-).)

Agreed! I wish that more languages allowed hyphen use in identifiers.
Dylan is the only one I can think of off the top of my head.

Lisp and Scheme.

Cobol

--
Chuck F (cb********@yah oo.com) (cb********@wor ldnet.att.net)
Available for consulting/temporary embedded and systems.
<http://cbfalconer.home .att.net> USE worldnet address!