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How to make the first option of selected with jQuery
...l($("#target option:first").val()); will work in IE6, because you are literally looking up the first value, and entering it as target's value. Two id lookups instead of one.
– Nicholi
Feb 4 '12 at 1:56
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Counting null and non-null values in a single query
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If I understood correctly you want to count all NULL and all NOT NULL in a column...
If that is correct:
SELECT count(*) FROM us WHERE a IS NULL
UNION ALL
SELECT count(*) FROM us WHERE a IS NOT NULL
Edited to have the full query, after reading the comments :]
S...
Javascript switch vs. if…else if…else
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Answering in generalities:
Yes, usually.
See More Info Here
Yes, because each has a different JS processing engine, however, in running a test on the site below, the switch always out performed the if, elseif on a large number of iterations.
Test site
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Best way to compare 2 XML documents in Java
I'm trying to write an automated test of an application that basically translates a custom message format into an XML message and sends it out the other end. I've got a good set of input/output message pairs so all I need to do is send the input messages in and listen for the XML message to come ou...
Why does 1==1==1 return true, “1”==“1”==“1” return true, and “a...
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@KonradGadzina: Strict equals will make all three functions return false.
– Jon
May 9 '14 at 10:18
1
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How can I pass command-line arguments to a Perl program?
...rbose); # flag
Alternatively, @ARGV is a special variable that contains all the command line arguments. $ARGV[0] is the first (ie. "string1" in your case) and $ARGV[1] is the second argument. You don't need a special module to access @ARGV.
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How to define a function in ghci across multiple lines?
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For guards (like your example), you can just put them all on one line and it works (guards do not care about spacing)
let abs n | n >= 0 = n | otherwise = -n
If you wanted to write your function with multiple definitions that pattern match on the arguments, like this:
fac...
The data-toggle attributes in Twitter Bootstrap
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It is a Bootstrap data attribute that automatically hooks up the element to the type of widget it is. Data-* is part of the html5 spec, and data-toggle is specific to Bootstrap.
Some Examples:
data-toggle="modal"
data-toggle="collapse"
data-toggle="dropdown"
data-toggle...
What's the difference between lapply and do.call?
I'm learning R recently and confused by two function: lapply and do.call . It seems that they're just similar to map function in Lisp. But why are there two functions with such a different name? Why doesn't R just use a function called map ?
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'this' vs $scope in AngularJS controllers
...rs?"
Short answer:
this
When the controller constructor function is called, this is the controller.
When a function defined on a $scope object is called, this is the "scope in effect when the function was called". This may (or may not!) be the $scope that the function is defined on. So, insi...