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Why dict.get(key) instead of dict[key]?
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It allows you to provide a default value if the key is missing:
dictionary.get("bogus", default_value)
returns default_value (whatever you choose it to be), whereas
dictionary["bogus"]
would raise a KeyError.
If omitted...
When do items in HTML5 local storage expire?
...may run into space considerations. It's good to program defensively. Generally however things remain "forever" based on some practical definition of that word.
edit — obviously, your own application can actively remove stuff if it decides it's too old. That is, you can explicitly include some so...
How to capture stdout output from a Python function call?
...o_something(my_object)
output is now a list containing the lines printed by the function call.
Advanced usage:
What may not be obvious is that this can be done more than once and the results concatenated:
with Capturing() as output:
print('hello world')
print('displays on screen')
with Ca...
How to pass values between Fragments
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I tried step 5, That i'm calling listactivity from fragment and after selecting item from that activity, i want to come back in fragment with selected file name. But its not working, its giving me Nullpointer Exception at onCreateView. Any solution on...
simple HTTP server in Java using only Java SE API
... GET/POST) in Java using just the Java SE API, without writing code to manually parse HTTP requests and manually format HTTP responses? The Java SE API nicely encapsulates the HTTP client functionality in HttpURLConnection, but is there an analog for HTTP server functionality?
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How to disable scrolling temporarily?
...e scrolling is that when you scroll while scrollTo is animating, it gets really ugly ;)
35 Answers
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Why malloc+memset is slower than calloc?
...The performance difference here is much larger (I measured more than three orders of magnitude on my system between malloc()+memset() and calloc()).
Party trick
Instead of looping 10 times, write a program that allocates memory until malloc() or calloc() returns NULL.
What happens if you add mems...
Why can't non-default arguments follow default arguments?
...wed. A SyntaxError is raised if the arguments are not given in the correct order:
Let us take a look at keyword arguments, using your function.
def fun1(a="who is you", b="True", x, y):
... print a,b,x,y
Suppose its allowed to declare function as above,
Then with the above declarations, we c...
How do you automatically set text box to Uppercase?
...le="text-transform:uppercase" />
<img src="../images/tickmark.gif" border="0" />
Please note this transformation is purely visual, and does not change the text that is sent in POST.
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Retrieve only the queried element in an object array in MongoDB collection
...r to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// Get just the docs that contain a shapes element where color is 'red'
{$match: {'shapes.color': 'red'}},
{$project: {
shapes: {$filter: {
...