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Is it safe to parse a /proc/ file?
...o. (So most of the answers here are wrong.) It might be safe, depending on what property you want. But it's easy to end up with bugs in your code if you assume too much about the consistency of a file in /proc. For example, see this bug which came from assuming that /proc/mounts was a consistent sna...
Is there a label/goto in Python?
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No, Python does not support labels and goto, if that is what you're after. It's a (highly) structured programming language.
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“is” operator behaves unexpectedly with integers
...; b = 257
>>> id(a)
11662816
>>> id(b)
11662828
Here's what I found in the Python 2 documentation, "Plain Integer Objects" (It's the same for Python 3):
The current implementation keeps an
array of integer objects for all
integers between -5 and 256, when you
create an ...
Use of def, val, and var in scala
...alue, it will just be discarded). In this line of code:
person.age = 20
what happens is that you first call the person method, and on the return value (an instance of class Person) you are changing the age member variable.
And the last line:
println(person.age)
Here you are again calling the...
What's the difference between using CGFloat and float?
...ing "heavier" than float, right? At which points should I use CGFloat, and what makes really the difference?
5 Answers
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Why is it not advisable to have the database and web server on the same machine?
...ed least privilege rules in connecting to your DB, the maximum exposure is what your app can do through the database API. If you have a business tier in between, you have one more step between your attacker and your data. If, on the other hand, your database is on the same server, the attacker now h...
Passing parameters to addTarget:action:forControlEvents
...message:
action:@selector(switchToNewsDetails:event:)
It is not clear what exactly you try to do, but considering you want to assign a specific details index to each button you can do the following:
set a tag property to each button equal to required index
in switchToNewsDetails: method you c...
What are Runtime.getRuntime().totalMemory() and freeMemory()?
I've been wondering what the exact meaning of Runtime.getRuntime().totalMemory() , Runtime.getRuntime().freeMemory() , and Runtime.getRuntime().maxMemory() is.
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Big-O for Eight Year Olds? [duplicate]
I'm asking more about what this means to my code. I understand the concepts mathematically, I just have a hard time wrapping my head around what they mean conceptually. For example, if one were to perform an O(1) operation on a data structure, I understand that the number of operations it has to p...
What is the difference between “INNER JOIN” and “OUTER JOIN”?
... of rows of Employee and Location are combined into a result row.
Here’s what the SQL for an inner join will look like:
select * from employee inner join location on employee.empID = location.empID
OR
select * from employee, location where employee.empID = location.empID
Now, here is what the...