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Best way to strip punctuation from a string
...s working with the same datatype, but the approach in this answer works equally well for both, which is handy.
– Richard J
Jan 16 '15 at 9:35
38
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How to throw an exception in C?
...and caught in the program, but the C code portions will remain ignorant of all of this going on except that exception throwing and catching often rely on functions written in C which reside in the C++ libraries. C is used because you can't risk the function called to do throw needing to throw an exc...
Python: most idiomatic way to convert None to empty string?
...
If you actually want your function to behave like the str() built-in, but return an empty string when the argument is None, do this:
def xstr(s):
if s is None:
return ''
return str(s)
...
What does the C++ standard state the size of int, long type to be?
... value of the CHAR_BIT macro that defines the number of bits in a byte. In all but the most obscure platforms it's 8, and it can't be less than 8.
One additional constraint for char is that its size is always 1 byte, or CHAR_BIT bits (hence the name). This is stated explicitly in the standard.
The C...
Why is there no xrange function in Python3?
...Some performance measurements, using timeit instead of trying to do it manually with time.
First, Apple 2.7.2 64-bit:
In [37]: %timeit collections.deque((x for x in xrange(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.05 s per loop
Now, python.org 3.3.0 64-bit:
In [83]: %timeit collec...
How do I import the Django DoesNotExist exception?
...y of the model itself, in this case Answer.
Your problem is that you are calling the get method - which raises the exception - before it is passed to assertRaises. You need to separate the arguments from the callable, as described in the unittest documentation:
self.assertRaises(Answer.DoesNotExis...
How to use the TextWatcher class in Android?
...ich are overridden for the text watcher. you can mask the text which you really wanted to.
– Dinesh Prajapati
Dec 17 '11 at 8:07
2
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How to read keyboard-input?
... mixing different Pythons here (Python 2.x vs. Python 3.x)...
This is basically correct:
nb = input('Choose a number: ')
The problem is that it is only supported in Python 3. As @sharpner answered, for older versions of Python (2.x), you have to use the function raw_input:
nb = raw_input('Choose...
Why are preprocessor macros evil and what are the alternatives?
I have always asked this but I have never received a really good answer; I think that almost any programmer before even writing the first "Hello World" had encountered a phrase like "macro should never be used", "macro are evil" and so on, my question is: why? With the new C++11 is there a real alte...
What is a proper naming convention for MySQL FKs?
...constraints. If a name is not given, InnoDB creates a unique name automatically.
In any case, this is the convention that I use:
fk_[referencing table name]_[referenced table name]_[referencing field name]
Example:
CREATE TABLE users(
user_id int,
name varchar(100)
);
CREATE T...