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From: VK on 6 Jun 2010 10:15
Recently discussions arose about CC, its authorship and usage
priority.

As an introduction I want to remind that the "obviousness" of
something doesn't make it automatically a community invention nor
implies its quick realization. The idea of stickers is damn obvious,
but only one person in the whole factory realized how to use the weak
glue produced by mistake.

The fact that something is well-know and commonly used doesn't
eliminate the fact that someone first did it and shared it with others
(or others saw it and copied). The idea of dynamic script insertion
using document.write(scriptTagWithSrc) is damn obvious and used by
nearly everyone. Yet Appeon Corporation from San Jose has proofs of
having it invented and first used which are convincing enough for the
US patent bureau: so many are using for years a patented technology:

http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=6941562.PN.&OS=PN/6941562&RS=PN/6941562
without paying patent fees only because of the good-hardness of Mr.
Gao Yang and Co. See also http://jsnet.sourceforge.net/

Now back to the CC: its core concept and usage samples were developed
in two independent works:
"Private Members in JavaScript" by Douglas Crockford (2001)
http://www.crockford.com/javascript/private.html
and
"Private Static Members in JavaScript" by Richard Cornford (2003)
The article is gone but still available over Wayback Machine:
http://web.archive.org/web/20031205082329/http://www.litotes.demon.co.uk/js_info/private_static.html
(In "Cornford-Crockford Scope Management" name order is alphabetical)

It became the "common knowledge everyone knows" with AJAX explosion,
when it became necessary to keep "this" pointer between state change
calls. Same time the first big wave of C++ and Java programmers was
forced to start working with JavaScript and they needed Her Majesty
Encapsulation immediately. Note: if something is not encapsulated, a
real C++'er or Java'er cannot eat, dring and sleep. She can create a
memory killing ineffective monstrosity and happy leave for the week-
end. If something left non-encapsulated, the week-end mood will be
spoiled completely. As a result CC became severely overused. This
madness is still in effect but thanks God lesser than in 2005-2006

CC Scope Management and its terminology didn't appear from nothing of
course. First of all nested functions never were kept in secret. They
were always mentioned in Client-Side JavaScript Reference at Netscape
Developer Center:
http://docs.sun.com/source/816-6408-10/function.htm#1225385
But they were just mentioned without any samples of how it could be
used and why. I have an impression - possibly a wrong one - that for
Netscape JavaScript team it remained just as a bizarre side effect of
the original design.

The first ever known to me use of the term "closure" in JavaScript
sense occurred not in JavaScript but Perl book. In August of 1998 the
1st ed. of "Perl Cookbook" by Tom Christiansen, Nathan Torkington
appeared in stores and became very popular. In that book the section
"10.16 Nesting Subroutines" describes nested functions in Perl:
<quote>
10.16 Nesting Subroutines
....
sub outer {
my $x = $_[0] + 35;
local *inner = sub { return $x * 19 };
return $x + inner();
}
....
Now inner() can be called only from within outer() because of the
temporary assignments of the closure.
</quote>

So it was plenty of sources and hints to make 2 and 2 together, yet
some people did it first.
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