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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...
Pass in an array of Deferreds to $.when()
...
To pass an array of values to any function that normally expects them to be separate parameters, use Function.prototype.apply, so in this case you need:
$.when.apply($, my_array).then( ___ );
See http://jsfiddle.net/YNGcm/21/
In ES6, you can use the ... spread operator ins...
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...
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)
...
Kotlin secondary constructor
...tructors in Kotlin since these constructors are necessary sometimes, especially when working with Java frameworks and extending Java classes. Hope you'll get them back soon.
– Michael
Jul 17 '14 at 7:46
...
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...
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...
Get name of object or class
...(function(){}); new myclass prints myclass {}
– Hugh Allen
May 26 '14 at 4:09
...
How do I create a copy of an object in PHP?
...ass by reference is a bad idea, because it makes the effect of a function call depend on the implementation of the function, rather than on the specification. It's got nothing to do with pass by value being the default.
– Oswald
Oct 4 '13 at 7:06
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