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Check if something is (not) in a list in Python
... @nightcracker That makes no sense as A not in B is reduced to doing not B.__contains__(A) which is the same as what not A in B is reduced to which is not B.__contains__(A).
– Dan D.
May 2 '12 at 0:33
...
python: How do I know what type of exception occurred?
...pe {0} occurred. Arguments:\n{1!r}"
message = template.format(type(ex).__name__, ex.args)
print message
Make sure message is brought to the attention of the user in a hard-to-miss way! Printing it, as shown above, may not be enough if the message is buried in lots of other messages. Failin...
Redirecting to URL in Flask
...eturn a redirect:
import os
from flask import Flask,redirect
app = Flask(__name__)
@app.route('/')
def hello():
return redirect("http://www.example.com", code=302)
if __name__ == '__main__':
# Bind to PORT if defined, otherwise default to 5000.
port = int(os.environ.get('PORT', 5000)...
Adding git branch on the Bash command prompt
...
git 1.9.3 or later: use __git_ps1
Git provides a shell script called git-prompt.sh, which includes a function __git_ps1 that
prints text to add to bash PS1 prompt (includes branch name)
Its most basic usage is:
$ __git_ps1
(master)
It also...
What is __stdcall?
...
__stdcall is the calling convention used for the function. This tells the compiler the rules that apply for setting up the stack, pushing arguments and getting a return value.
There are a number of other calling conventions...
How do I add a placeholder on a CharField in Django?
...t specify the field (e.g. for some dynamic method), you can use this:
def __init__(self, *args, **kwargs):
super(MyForm, self).__init__(*args, **kwargs)
self.fields['email'].widget.attrs['placeholder'] = self.fields['email'].label or 'email@address.nl'
It also allows the placeholder to de...
What is the formal difference in Scala between braces and parentheses, and when should they be used?
...e method expects a single parameter. For example:
List(1, 2, 3).reduceLeft{_ + _} // valid, single Function2[Int,Int] parameter
List{1, 2, 3}.reduceLeft(_ + _) // invalid, A* vararg parameter
However, there’s more you need to know to better grasp these rules.
Increased compile checking with pare...
Batch files - number of command line arguments
... handle number of arguments with this sort of logic:
IF "%1"=="" GOTO HAVE_0
IF "%2"=="" GOTO HAVE_1
IF "%3"=="" GOTO HAVE_2
etc.
If you have more than 9 arguments then you are screwed with this approach though. There are various hacks for creating counters which you can find here, but be warne...
How can I swap positions of two open files (in splits) in vim?
...
Starting with this:
____________________
| one | two |
| | |
| |______|
| | three|
| | |
|___________|______|
Make 'three' the active window, then issue the command ctrl+w J. This moves ...
Comparing strings with == which are declared final in Java
...llowing byte code:
Code:
0: ldc #2; //String str
2: astore_1
3: ldc #3; //String ing
5: astore_2
6: new #4; //class java/lang/StringBuilder
9: dup
10: invokespecial #5; //Method java/lang/StringBuilder."<init>":()V
13: aload_1
14: invo...
