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How to use Active Support core extensions
...oose to load bigger chunks. If you want everything in one big gulp use...
For 1.9.2:
rvm 1.9.2
irb -f
irb(main):001:0> require 'active_support/all'
=> true
irb(main):002:0> 1.week.ago
=> 2010-11-14 17:56:16 -0700
irb(main):003:0>
For 1.8.7:
rvm 1.8.7
irb -f
irb(main):001:0> r...
Count the occurrences of DISTINCT values
...
While Amber's query is the correct answer for the question, I would like to make a correction on her comment to avoid leading new people astray. If you leave off the "group by" in a MySQL query, you don't get [Mike, 1], [Mike, 1], you get a single result which will...
How to see if an object is an array without using reflection?
...{
return obj!=null && obj.getClass().isArray();
}
This works for both object and primitive type arrays.
For toString take a look at Arrays.toString. You'll have to check the array type and call the appropriate toString method.
...
What’s the difference between “Array()” and “[]” while declaring a JavaScript array?
...s the stack size. This can be useful if you're getting stack overflows (Performance of Array.push vs Array.unshift) which is what happens when the size of the array exceeds the size of the stack, and it has to be re-created. So there can actually, depending on the use case, be a performance increase...
How to create an array of 20 random bytes?
...
For those wanting a more secure way to create a random byte array, yes the most secure way is:
byte[] bytes = new byte[20];
SecureRandom.getInstanceStrong().nextBytes(bytes);
BUT your threads might block if there is not en...
CSS: Control space between bullet and
...clarify, the <span> tag can be semantic when it is assigned a class, for instance <span class="tel">123-456-7890</span> is implicitly semantic.
– ingyhere
Mar 2 '12 at 2:01
...
Force Screen On
How do I force the screen to stay active and not shut off while my app is running?
3 Answers
...
What's wrong with overridable method calls in constructors?
...te.
A quote from Effective Java 2nd Edition, Item 17: Design and document for inheritance, or else prohibit it:
There are a few more restrictions that a class must obey to allow inheritance. Constructors must not invoke overridable methods, directly or indirectly. If you violate this rule, prog...
Why does the lock object have to be static?
It is very common to use a private static readonly object for locking in multi threading.
I understand that private reduces the entry points to the locking object by tightening the encapsulation and therefore access to the most essential.
...
Stop pip from failing on single package when installing with requirements.txt
...
for mac: cat requirements.txt | xargs -n 1 pip install
– Walty Yeung
Sep 4 '16 at 1:32
5
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