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Why does i = i + i give me 0?
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230 + 230 = -231
-231 + -231 = 0
...in int arithmetic, since it's essentially arithmetic mod 2^32.
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Can enums be subclassed to add new elements?
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If you could tell us more about how you want to use this, we could potentially suggest alternative solutions.
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How to scale a UIImageView proportionally?
I have a UIImageView and the objective is to scale it down proportionally by giving it either a height or width.
17 Answer...
How do I convert array of Objects into one Object in JavaScript?
... item.value, obj) ,{});
Here we benefit from comma operator, it evaluates all expression before comma and returns a last one(after last comma). So we don't copy obj each time, rather assigning new property to it.
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Where are iOS simulator screenshots stored?
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For me, there's nothing in that folder. It's all on the Desktop. Not sure why? :/
– chakrit
Feb 9 '12 at 6:21
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Android file chooser [closed]
...tent in an Intent.createChooser() like this:
private static final int FILE_SELECT_CODE = 0;
private void showFileChooser() {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("*/*");
intent.addCategory(Intent.CATEGORY_OPENABLE);
try {
startActivityFor...
How to use “raise” keyword in Python [duplicate]
...dler, so that it can be handled further up the call stack.
try:
generate_exception()
except SomeException as e:
if not can_handle(e):
raise
handle_exception(e)
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Pip freeze vs. pip list
...you are using a virtualenv, you can specify a requirements.txt file to install all the dependencies.
A typical usage:
$ pip install -r requirements.txt
The packages need to be in a specific format for pip to understand, which is
feedparser==5.1.3
wsgiref==0.1.2
django==1.4.2
...
That is the ...
What does the smiley face “:)” mean in CSS?
...wsers.
Also there's a hack for <= IE 8:
div {
color: blue; /* All browsers */
color: purple\9; /* IE8 and earlier */
*color: pink; /* IE7 and earlier */
}
However that's not a good idea, they don't validate. You always feel free to work with Conditional comments for targeting...
Difference between Destroy and Delete
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Basically destroy runs any callbacks on the model while delete doesn't.
From the Rails API:
ActiveRecord::Persistence.delete
Deletes the record in the database and freezes this instance to reflect that no changes should be ...