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Rank function in MySQL
... (SELECT @curRank := 0) r
ORDER BY age;
The (SELECT @curRank := 0) part allows the variable initialization without requiring a separate SET command.
Test case:
CREATE TABLE person (id int, first_name varchar(20), age int, gender char(1));
INSERT INTO person VALUES (1, 'Bob', 25, 'M');
INSERT I...
How to exit from Python without traceback?
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If sys.exit() is called in "main program stuff", the code above throws away the value passed to sys.exit. Notice that sys.exit raises SystemExit and the variable "e" will contain the exit code.
– bstpierre
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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...
Hidden features of C
I know there is a standard behind all C compiler implementations, so there should be no hidden features. Despite that, I am sure all C developers have hidden/secret tricks they use all the time.
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Inserting a tab character into text using C#
...re than one TextBox are displayed and that alignment must be respected for all TextBox, the ONLY "\t" or vbTab solution will display something that is NOT ALWAYS correctly aligned.
Example in VB.Net:
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
TextBox1.Text = ...
Get full path of the files in PowerShell
I need to get all the files including the files present in the subfolders that belong to a particular type.
14 Answers
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error: ‘uint16_t’ does not name a type - C/C++ - 清泛网 - 专注C/C++及内核技术
...ght notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHA...
Wolfram's Rule 34 in XKCD [closed]
The hover "joke" in #505 xkcd touts "I call rule 34 on Wolfram's Rule 34".
12 Answers
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What is the purpose of the single underscore “_” variable in Python?
...cate that part
of a function result is being deliberately ignored (Conceptually, it is being discarded.), as in code like:
label, has_label, _ = text.partition(':').
As part of a function definition (using either def or lambda), where
the signature is fixed (e.g. by a callback or parent class API), ...
Reference: What is variable scope, which variables are accessible from where and what are “undefined
... be in the global scope in a.php doesn't necessarily mean they are, it actually depends on which context that code is included/executed in.
What about functions inside functions and classes?
Every new function declaration introduces a new scope, it's that simple.
(anonymous) functions inside func...