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What reason is there to use null instead of undefined in JavaScript?
I've been writing JavaScript for quite a long time now, and I have never had a reason to use null . It seems that undefined is always preferable and serves the same purpose programmatically. What are some practical reasons to use null instead of undefined ?
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Consistency of hashCode() on a Java string
... you shouldn't rely on a hash code implementation remaining the same, it's now documented behaviour for java.lang.String, so changing it would count as breaking existing contracts.
Wherever possible, you shouldn't rely on hash codes staying the same across versions etc - but in my mind java.lang.St...
MySQL COUNT DISTINCT
... countVisits
, site_id As site
From cp_visits
Where ts >= DATE_SUB(NOW(), INTERVAL 1 DAY)
Group By site_id
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What does GitHub for Windows' “sync” do?
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Can confirm hitting Sync just now did a git pull rather than a git pull --rebase, thus creating an additional Merge branch 'master' of ... commit.
– Leo
Sep 9 '16 at 14:33
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When to use self over $this?
...I did get some more information that I found helpful further down, but for now I was just trying to figure out why I hit my class attributes with $this->attrib and the class constants with self::constant. This helped me understand that better
– MydKnight
Jul...
How can I get the SQL of a PreparedStatement?
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It's nowhere definied in the JDBC API contract, but if you're lucky, the JDBC driver in question may return the complete SQL by just calling PreparedStatement#toString(). I.e.
System.out.println(preparedStatement);
At least MyS...
What is __init__.py for?
...make two blank files, the init.py file (with underscores) and datetime.py. Now open an interpreter, import sys, and issue sys.path.insert(0, '/path/to/datetime'), replacing that path with the path to whatever directory you just made. Now try something like from datetime import datetime;datetime.now(...
Multiple github accounts on the same computer?
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The 3rd link is now broken (Multiple SSH Keys)
– RustyTheBoyRobot
Jun 1 '12 at 14:25
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Fastest way to determine if an integer is between two integers (inclusive) with known sets of values
...does a comparison of resulting assembler and profiling info). For all we know, the OP's compiler may render the OP's code with a single branch opcode...
– Oliver Charlesworth
Jun 13 '13 at 19:50
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Font size in CSS - % or em?
...on /. about that (and lost). I had the same point of view as you, good to know someone shares that pov :)
– Vincent McNabb
Sep 25 '08 at 11:24
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