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How can I explicitly free memory in Python?
... In general, gc.collect() is to be avoided. The garbage collector knows how to do its job. That said, if the OP is in a situation where he is suddenly deallocating a lot of objects (like in the millions), gc.collect may prove useful.
– Jason Baker
Aug ...
How do I hide a menu item in the actionbar?
...be null because you are using getItem instead of findItem. We could never know, without seeing both your code and crash log.
– K-ballo
May 21 '12 at 21:31
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Why generate long serialVersionUID instead of a simple 1L?
...glected to use a serialVersionUID before, and then made a change that you know should be compatible but which causes serialization to break.
See the Java Serialization Spec for more details.
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Java recursive Fibonacci sequence
... fibonacci(3) + fibonacci(2)
fibonacci(2) = fibonacci(1) + fibonacci(0)
Now you already know fibonacci(1)==1 and fibonacci(0) == 0. So, you can subsequently calculate the other values.
Now,
fibonacci(2) = 1+0 = 1
fibonacci(3) = 1+1 = 2
fibonacci(4) = 2+1 = 3
fibonacci(5) = 3+2 = 5
And from fi...
How do I grep for all non-ASCII characters?
... no longer supports PCRE ("Perl-compatible regular expressions") as Darwin now uses BSD grep instead of GNU grep. An alternative to installing the dupes library is to install pcre instead: brew install pcre... as part of this, you will get the pcregrep utility, which you can use as follows: pcregrep...
Call a global variable inside module
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For those who didn't know already, you would have to put the declare statement outside your class just like this:
declare var Chart: any;
@Component({
selector: 'my-component',
templateUrl: './my-component.component.html',
styleUrls: ['./m...
The “unexpected ++” error in jslint [duplicate]
...meone comes along and moves the space?
var i = 0, j = 0;
alert(i+ ++j);
Now this first increments j, and then adds i to the new value of j, resulting in 1 being alerted.
This could easily be solved by doing
var i = 0, j = 0;
alert((i++) +j);
Now this cannot be mistaken.
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How do I perform the SQL Join equivalent in MongoDB?
...mmend specific use cases for $lookup, but at least as of 3.2 doing join is now possible with MongoDB.
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How do I adjust the anchor point of a CALayer, when Auto Layout is being used?
...he view to vanish from the screen, since autolayout still takes place, and now there are no constraints to tell us where to put the view. So in addition to removing the constraints, I set the view's translatesAutoresizingMaskIntoConstraints to YES. The view now works in the old way, effectively unaf...
Getting the name of the currently executing method
...at a lot of work has gone into making HotSpot very reliable. You need to know, though, in case you want your code to not rely on the behavior of a specific JVM.
– Thorbjørn Ravn Andersen
Apr 15 '13 at 8:53
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