2010-11-14

the various uses of double-colon

 10.2: news.adda/dstr/:: as conversion in Axiom:
 The :: is used here to change from one kind of object
 (here, a rational number) to another (a floating-point number).
r::Float .
. the aldor.lang` tutorial shows
the same is true of aldor.lang  too .

10.13: news.adda/dstr/use of :: or misparsing javascript:

var anchors = $x('//h3/font/b[text()="[PDF]"]/parent::*/parent::*/a')
... I may be misparsing;
this could be separating places by a colon,
but the things being separated are colon-terminated tags .

10.14: news.adda/[perl`::]:
Perl's Win32::GuiTest module
10.18: mathforum.org:
. it is not a bad thing to have your module name
include two colons, as in the name
Text::Wrap.
When this module is installed,
it will be placed in a directory named Text
under the root library directory.
The module code itself will be in a file called Wrap.pm .
This helps keep the library directory more organized.
In addition, the :: naming convention
can also indicate class hierarchies,
although it does not have to.
11.14: keyword double-colon:

. it's the scope resolution operator
in php and c++, eg, class::function
. c++'s default class is the global space:
::global -- found outside any function block .
. that way the function's block can shadow a global's name,
and then still access that global .

. the php`err.msg's call "(::) a Paamayim Nekudotayim,
(Hebrew for double colon).

gnu`make`::
Double-colon rules are explicit rules
handled differently from ordinary rules
when the same target appears in
more than one rule.
Pattern rules with double-colons
have an entirely different meaning:
if the rules are of type double-colon,
each of them is independent of the others.
. the cases where double-colon rules really make sense
are those where the order of executing the recipes
would not matter.
. they provide a mechanism for the rare cases
in which the method used to update a target
differs depending on which prerequisite files
caused the update .
HP OpenVMS`DECset`DIGITAL Module Management System`
. "(::) means additionally_depends_on .

ipv6 email syntax:
. it can have 8 words (16bit values)
separated by colons;
a double colon means missing values,
assumed to be zero .
the bible of SMTP, RFC 5321:
“The “::” represents at least 2 zero words.
the bible of IPv6, RFC 4291:
“The use of “::” indicates one or more zero words .”
RFC 5952 :
The symbol “::” MUST NOT be used for just one zero word .

"(::) is a contraction over four indices,
-- like when a colon means
a tensor contraction involving 2 indices .

a font for an audiovisual within dialog:
. everything was fine ::click:: . oh .