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Extract substring in Bash
...o-based) and "5" is the length. Also, +1 for @gontard 's link that lays it all out!
– Doktor J
Sep 12 '14 at 17:32
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SQLAlchemy: cascade delete
...use that is where you defined your relationship (it doesn't care that you called it "Child" of course).
If you define the relationship on the Parent class instead, it will work:
children = relationship("Child", cascade="all,delete", backref="parent")
(note "Child" as a string: this is allowed wh...
How to plot two columns of a pandas data frame using points?
...
You can specify the style of the plotted line when calling df.plot:
df.plot(x='col_name_1', y='col_name_2', style='o')
The style argument can also be a dict or list, e.g.:
import numpy as np
import pandas as pd
d = {'one' : np.random.rand(10),
'two' : np.random.rand(...
Calling Objective-C method from C++ member function?
I have a class ( EAGLView ) which calls a member function of a C++ class without problems. Now, the problem is that I need to call in that C++ class a objective-C function [context renderbufferStorage:GL_RENDERBUFFER fromDrawable:(CAEAGLLayer*)self.layer]; which I cannot do in C++ syntax...
Pragma in define macro
...ay of doing that. Then again, there are no portable ways to use #pragma at all. Because of this, many C/C++ compilers define their own methods for doing pragma-like things, and they often can be embedded in macros, but you need a different macro definition on every compiler. If you are willing to go...
Are there legitimate uses for JavaScript's “with” statement?
...ous as to how I might make effective use of with , while avoiding its pitfalls.
31 Answers
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What is the difference between a field and a property?
...sed via get and set properties. Properties provide a level of abstraction allowing you to change the fields while not affecting the external way they are accessed by the things that use your class.
public class MyClass
{
// this is a field. It is private to your class and stores the actual da...
how to detect search engine bots with php?
...ming to them. It also depends on utility. I wouldn't use this to strip out all CSS, but I would use this to not store cookies, ignore location logging, or skip a landing page.
– JonShipman
Mar 26 '15 at 21:28
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What does enumerate() mean?
...ieving that; one using itertools.count() to do the counting, the other manually counting in a generator function:
from itertools import count
def enumerate(it, start=0):
# return an iterator that adds a counter to each element of it
return zip(count(start), it)
and
def enumerate(it, sta...
Union of dict objects in Python [duplicate]
...yptic, and it immediately makes most readers balk and the remainder assume all the keys in x would have to be legal parameter names. IMHO, the fact it works is a bug in the name-checking mechanisms in the implementation. What happens when you rely on bugs? They either get fixed, or become politic...