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How exactly does tail recursion work?
I almost understand how tail recursion works and the difference between it and a normal recursion. I only don't understand why it doesn't require stack to remember its return address.
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Python JSON serialize a Decimal object
...ld mean a yield on the line with super(...),
# which wouldn't work (see my comment below), so...
return (str(o) for o in [o])
return super(DecimalEncoder, self).default(o)
Then use it like so:
json.dumps({'x': decimal.Decimal('5.5')}, cls=DecimalEncoder)
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How to check for a valid Base64 encoded string
... 64 encoded other than just trying to convert it and see if there is an error? I have code code like this:
19 Answers
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Hide scroll bar, but while still being able to scroll
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Just a test which is working fine.
#parent{
width: 100%;
height: 100%;
overflow: hidden;
}
#child{
width: 100%;
height: 100%;
overflow-y: scroll;
padding-right: 17px; /* Increase/decrease this value for cross-browser c...
How to repeat a string a variable number of times in C++?
I want to insert 'n' spaces (or any string) at the beginning of a string in C++. Is there any direct way to do this using either std::strings or char* strings?
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What's the difference between KeyDown and KeyPress in .NET?
... resulting from a keypress, and is only called if there is one.
In other words, if you press A on your keyboard, you'll get this sequence of events:
KeyDown: KeyCode=Keys.A, KeyData=Keys.A, Modifiers=Keys.None
KeyPress: KeyChar='a'
KeyUp: KeyCode=Keys.A
But if you press Shift+A, you'll get:
K...
pdftk compression option
...I had the same problem and found two different solutions (see this thread for more details). Both reduced the size of my uncompressed PDF dramatically.
Pixelated (lossy):
convert input.pdf -compress Zip output.pdf
Unpixelated (lossless, but may display slightly differently):
gs -sDEVICE=pdfwri...
How to convert from System.Enum to base integer?
I'd like to create a generic method for converting any System.Enum derived type to its corresponding integer value, without casting and preferably without parsing a string.
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Are typedef and #define the same in c?
...
No.
#define is a preprocessor token: the compiler itself will never see it.
typedef is a compiler token: the preprocessor does not care about it.
You can use one or the other to achieve the same effect, but it's better to use the proper one for your n...
Python Progress Bar
...braries (like this one here) but maybe something very simple would do:
import time
import sys
toolbar_width = 40
# setup toolbar
sys.stdout.write("[%s]" % (" " * toolbar_width))
sys.stdout.flush()
sys.stdout.write("\b" * (toolbar_width+1)) # return to start of line, after '['
for i in xrange(too...