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How is Python's List Implemented?
...dynamic array. Practical proof: Indexing takes (of course with extremely small differences (0.0013 µsecs!)) the same time regardless of index:
...>python -m timeit --setup="x = [None]*1000" "x[500]"
10000000 loops, best of 3: 0.0579 usec per loop
...>python -m timeit --setup="x = [None]*100...
findViewById in Fragment
...e fragment (the one returned by onCreateView() method). With this you can call findViewById().
@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
ImageView imageView = (ImageView) getView().findViewById(R.id.foo);
// or (ImageView) view.findViewById(R.id....
twitter bootstrap typeahead ajax example
...ample of the twitter bootstrap typeahead element that will make an ajax call to populate it's dropdown.
16 Answers
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Oracle Differences between NVL and Coalesce
...ented differently.
NVL always evaluates both arguments, while COALESCE usually stops evaluation whenever it finds the first non-NULL (there are some exceptions, such as sequence NEXTVAL):
SELECT SUM(val)
FROM (
SELECT NVL(1, LENGTH(RAWTOHEX(SYS_GUID()))) AS val
FROM dual
...
object==null or null==object?
... {
The convention of putting the constant on the left side of == isn't really useful in Java since Java requires that the expression in an if evaluate to a boolean value, so unless the constant is a boolean, you'd get a compilation error either way you put the arguments. (and if it is a boolean, y...
Default string initialization: NULL or Empty? [closed]
... Distinguishing between NULL and empty is great when there is actually a difference between the two. There are many cases, though, where there is not a difference, and thus having two ways of representing the same thing is a liability.
– Greg Smalter
...
return, return None, and no return at all?
...
On the actual behavior, there is no difference. They all return None and that's it. However, there is a time and place for all of these.
The following instructions are basically how the different methods should be used (or at least how I was taught they should be used), but th...
What's the difference between isset() and array_key_exists()? [duplicate]
How do the following two function calls compare:
8 Answers
8
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Alternate FizzBuzz Questions [closed]
...
I've seen a small list of relatively simple programming problems used to weed out candidates, just like FizzBuzz. Here are some of the problems I've seen, in order of increasing difficulty:
Reverse a string
Reverse a sentence ("bob likes...
How to create a new (and empty!) “root” branch?
...ository. By "root" branch I mean a branch that is entirely independent of all the other branches in the repository 1 .
4 A...