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Use of alloc init instead of new
...selected ones are:
new doesn't support custom initializers (like initWithString)
alloc-init is more explicit than new
General opinion seems to be that you should use whatever you're comfortable with.
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If vs. Switch Speed
...ector to look at the code produced, you will see that for huge switches on strings, the compiler will actually generate code that uses a hash table to dispatch these. The hash table uses the strings as keys and delegates to the case codes as values.
This has asymptotic better runtime than lots of c...
Check if a value is an object in JavaScript
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@Tresdin The best way is to run Object.prototype.toString.call(yourVar), being yourVar what you need to inspect. In case of arrays, Object.prototype.toString.call([1,2]) returns [object Array]
– Jose Rui Santos
Feb 25 '16 at 9:48
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Printing 1 to 1000 without loop or conditionals
...es, blowing up the code size, right? You might as well generate the output string itself instead of a thousand printfs.
– Darius Bacon
Jan 3 '11 at 8:44
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What is a good reason to use SQL views?
... T_NEW) but one that has data for both active and inactive users, with one extra column active.
If your system(s) have gazillion queries that do SELECT whatever FROM T_OLD WHERE whatever, you have two choices for the roll-out:
1) Cold Turkey - Change the DB, and at the same time, change, test and ...
HTML5 canvas ctx.fillText won't do line breaks?
...les i am using the measureText() method which shows how long (in pixels) a string will be when printed.
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Difference between HashMap, LinkedHashMap and TreeMap
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private TreeMap<String ,Integer> mySection2 = new TreeMap<>(); mySection2.put("abc1", 2); mySection2.put("abc2",5); mySection2.put("abc3",3); ...
What's wrong with nullable columns in composite primary keys?
...s version the "ext" part of the tuple is NOT NULL but defaults to an empty string -- which is semantically (and practically) different from a NULL. A NULL is an unknown, whereas an empty string is a deliberate record of "something not being present". In other words, "empty" and "null" are different ...
How to drop rows of Pandas DataFrame whose value in a certain column is NaN
...ilippSchwarz This error occurs if the column (EPS in the example) contains strings or other types that cannot be digested by np.isfinite(). I recommend to use pandas.notnull() that will handle this more generously.
– normanius
Apr 5 '18 at 10:02
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How to install the Raspberry Pi cross compiler on my Linux host machine?
...ow you should be able to compile your cmake programs simply by adding this extra flag: -D CMAKE_TOOLCHAIN_FILE=$HOME/raspberrypi/pi.cmake.
Using a cmake hello world example:
git clone https://github.com/jameskbride/cmake-hello-world.git
cd cmake-hello-world
mkdir build
cd build
cmake -D CMAKE_TO...