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Why do we need virtual functions in C++?
... a rat."
So far so good, right? Animals eat generic food, cats eat rats, all without virtual.
Let's change it a little now so that eat() is called via an intermediate function (a trivial function just for this example):
// This can go at the top of the main.cpp file
void func(Animal *xyz) { xyz-...
How to change a module variable from another module?
...conduct your experiment there by setting bar.a = 1. This way, you will actually be modifying bar.__dict__['a'] which is the 'real' value of a in this context.
It's a little convoluted with three layers but bar.a = 1 changes the value of a in the module called bar that is actually derived from __ini...
Is gcc 4.8 or earlier buggy about regular expressions?
..., it is not implemented.
That prototype <regex> code was added when all of GCC's C++0x support was highly experimental, tracking early C++0x drafts and being made available for people to experiment with. That allowed people to find problems and give feedback to the standard committee before t...
Remove characters except digits from string using Python?
How can I remove all characters except numbers from string?
15 Answers
15
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Flask-SQLAlchemy import/context issue
...:
# fields here
pass
And then in your application setup you can call init_app:
# apps.application.py
from flask import Flask
from apps.members.models import db
app = Flask(__name__)
# later on
db.init_app(app)
This way you can avoid cyclical imports.
This pattern does not necessitate ...
How to open link in new tab on html?
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The special targets all start with an underscore. blank would be the name of a frame or window. It may seem to work, because a new window or tab will probably be opened when none exists with the name 'blank', but a second click on the link shoul...
Stop pip from failing on single package when installing with requirements.txt
I am installing packages from requirements.txt
6 Answers
6
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How to filter NSFetchedResultsController (CoreData) with UISearchDisplayController/UISearchBar
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I actually just implemented this on one of my projects (your question and the other wrong answer hinted at what to do). I tried Sergio's answer but had exception issues when actually running on a device.
Yes you create two fetch ...
In a django model custom save() method, how should you identify a new object?
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Not all models have an id attribute, i.e. a model extending another through a models.OneToOneField(OtherModel, primary_key=True). I think you need to use self.pk
– AJP
Apr 9 '13 at 10:21
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How to replace a hash key with another key
...n't like "smart" ruby code because it takes some time to tell what it is really doing. Your solution is in other hand simple and descriptive.
– Lucas
Nov 13 '14 at 18:55
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