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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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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) ...
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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...
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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...
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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...
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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...
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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 ...
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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...
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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...
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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 ...