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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)
...
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...
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...
Unit tests vs Functional tests
...- testing an individual unit, such as a method (function) in a class, with all dependencies mocked up.
Functional Test - AKA Integration Test, testing a slice of functionality in a system. This will test many methods and may interact with dependencies like Databases or Web Services.
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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...
Differences between dependencyManagement and dependencies in Maven
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Dependency Management allows to consolidate and centralize the management of dependency versions without adding dependencies which are inherited by all children. This is especially useful when you have a set of projects (i.e. more than one) that i...
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...
Remove duplicates from an array of objects in JavaScript
...) dot notation. Yours is ES5 syntax. The others are mostly ES6 (ECMA2015). All are valid in 2017. See jaredwilli's comment.
– agm1984
Nov 15 '17 at 9:20
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