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Best practice for Python assert
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To be able to automatically throw an error when x become less than zero throughout the function. You can use class descriptors. Here is an example:
class LessThanZeroException(Exception):
pass
class variable(object):
def __init__(self, va...
What does it mean if a Python object is “subscriptable” or not?
Which types of objects fall into the domain of "subscriptable"?
6 Answers
6
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What are metaclasses in Python?
...ass is an instance of a metaclass.
While in Python you can use arbitrary callables for metaclasses (like Jerub shows), the better approach is to make it an actual class itself. type is the usual metaclass in Python. type is itself a class, and it is its own type. You won't be able to recreate somet...
How to color System.out.println output? [duplicate]
...minals simply won't support some (if any) ANSI escape sequences and, especially, 24-bit colors.
Usage
Please refer to the section Curses at the bottom for the best solution. For a personal or easy solution (although not as cross-platform solution), refer to the ANSI Escape Sequences section.
TL...
Value Change Listener to JTextField
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I was having issues with a JTable not getting text box updates from an editable JComboBox when clicking another table cell, and the insertUpdate function here was the only way to make it work properly.
– winchella
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Scala 2.8 breakOut
...breakOut itself. It is of type CanBuildFrom[Nothing,T,To]. We already know all these types, so we can determine that we need an implicit of type CanBuildFrom[Nothing,(Int,String),Map[Int,String]]. But is there such a definition?
Let's look at CanBuildFrom's definition:
trait CanBuildFrom[-From, -E...
What are '$$' used for in PL/pgSQL
...is +999 999'';
END IF;
RETURN true;
END
' LANGUAGE plpgsql STRICT IMMUTABLE;
This isn't such a good idea. Use dollar-quoting instead, more specifically also put a token between the $$ to make it unique - you might want to use $-quotes inside the function body, too. I do that a lot, actually.
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Why doesn't list have safe “get” method like dictionary?
...accessing list elements (as the len method is very fast). The .get method allows you to query the value associated with a name, not directly access the 37th item in the dictionary (which would be more like what you're asking of your list).
Of course, you can easily implement this yourself:
def sa...
How to access outer class from an inner class?
...d Jan 7 '10 at 23:54
Daniel VassalloDaniel Vassallo
301k6666 gold badges475475 silver badges424424 bronze badges
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Bidirectional 1 to 1 Dictionary in C#
...turn firstToSecond.Count; }
}
/// <summary>
/// Removes all items from the dictionary.
/// </summary>
public void Clear()
{
firstToSecond.Clear();
secondToFirst.Clear();
}
}
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