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Django South - table already exists
...
Although the table "myapp_tablename" already exists error stop raising
after I did ./manage.py migrate myapp --fake, the DatabaseError shows
no such column: myapp_mymodel.added_field.
Got exactly the same problem!
1.Firstly check the migration...
Remove ActiveRecord in Rails 3
...r config/application.rb doesn't have require 'rails/all' or require "active_record/railtie". Instead, for a standard Rails setup without ActiveRecord, it should have only the following requires:
require File.expand_path('../boot', __FILE__)
require "action_controller/railtie"
require "action_maile...
How do I shuffle an array in Swift?
...Distance` in < Swift 4.1
let d: Int = numericCast(arc4random_uniform(numericCast(unshuffledCount)))
let i = index(firstUnshuffled, offsetBy: d)
swapAt(firstUnshuffled, i)
}
}
}
extension Sequence {
/// Returns an array with the contents of this...
Rename multiple files in a directory in Python [duplicate]
...e os.rename(src, dst) to rename or move a file or a directory.
$ ls
cheese_cheese_type.bar cheese_cheese_type.foo
$ python
>>> import os
>>> for filename in os.listdir("."):
... if filename.startswith("cheese_"):
... os.rename(filename, filename[7:])
...
>>>
$ ls
c...
Comments in Android Layout xml
...hem inside tags
<EditText <!--This is not valid--> android:layout_width="fill_parent" />
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What generates the “text file busy” message in Unix?
...tanding the underlying API to better see what is going on.
sleep.c
#define _XOPEN_SOURCE 700
#include <unistd.h>
int main(void) {
sleep(10000);
}
busy.c
#define _XOPEN_SOURCE 700
#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <sys/types.h>
#inc...
Get item in the list in Scala?
...y(Array(1, 2, 3), Array(4, 5, 6))
// 1. paratheses
scala> a.map(_(0))
Array[String] = Array(1, 4)
// 2. apply
scala> a.map(_.apply(0))
Array[String] = Array(1, 4)
// 3. function literal
scala> a.map(a => a(0))
Array[String] = Array(1, 4)
// 4. lift
scala> a.m...
What should main() return in C and C++?
...
stdlib.h provides EXIT_SUCCESS and EXIT_FAILURE for this purpose
– Clay
Oct 15 '08 at 13:13
21
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How can I create an object and add attributes to it?
... set on it. (I wish it could, for this exact purpose.) It doesn't have a __dict__ to hold the attributes.
I generally just do this:
class Object(object):
pass
a = Object()
a.somefield = somevalue
When I can, I give the Object class a more meaningful name, depending on what kind of data I'...
Sorting list based on values from another list?
...
Shortest Code
[x for _,x in sorted(zip(Y,X))]
Example:
X = ["a", "b", "c", "d", "e", "f", "g", "h", "i"]
Y = [ 0, 1, 1, 0, 1, 2, 2, 0, 1]
Z = [x for _,x in sorted(zip(Y,X))]
print(Z) # ["a", "d", "h", "b", "c", "e", "i", "f"...