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Is there a “null coalescing” operator in JavaScript?
...Boolean(null)); // false
alert(Boolean(undefined)); // false
alert(Boolean(0)); // false
alert(Boolean("")); // false
alert(Boolean("false")); // true -- gotcha! :)
This means:
var whatIWant = null || new ShinyObject(); // is a new shiny object
var whatIWant = undefined || "well defined"; // is "...
Rails 4: before_filter vs. before_action
In rails >4.0.0 generators creates CRUD operations with before_action not before_filter . It seems to do the same thing. So what's the difference between these two?
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how to make svn diff show only non-whitespace line changes between two revisions
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You can use
svn diff -r 100:200 -x -b > file.diff
If you want to ignore all whitespaces:
svn diff -x -w | less
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Does Internet Explorer support pushState and replaceState?
...ormation is CanIUse. Here's the section on history.
Summary - IE9: no, IE10: yes (as of platform preview 3)
The first Release Candidate of IE9 (released 10th Feb 2011) does not support history.pushState or history.replaceState. Generally no new features are added after a product gets to RC stage s...
Deprecated ManagedQuery() issue
... FemiFemi
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How do I create a SHA1 hash in ruby?
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answered Aug 29 '08 at 15:56
devstopfixdevstopfix
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Difference between doseq and for in Clojure
... sure did.
– Yu Shen
Jun 18 '14 at 10:23
This is a great way to put the distinction.
– jskulski
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SQL Server CTE and recursion example
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I haven't tested your code, just tried to help you understand how it operates in comment;
WITH
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IN vs OR in the SQL WHERE Clause
... your specific data to see which is faster.
I tried both on a MySQL with 1000000 rows. When the column is indexed there is no discernable difference in performance - both are nearly instant. When the column is not indexed I got these results:
SELECT COUNT(*) FROM t_inner WHERE val IN (1000, 2000, ...
Can I add comments to a pip requirements file?
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edited Jun 10 at 6:09
V. K.
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