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error: ‘NULL’ was not declared in this scope
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NULL is not a keyword. It's an identifier defined in some standard headers. You can include
#include <cstddef>
To have it in scope, including some other basics, like std::size_t.
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Flask-SQLAlchemy import/context issue
...y
db = SQLAlchemy()
class Member(db.Model):
# 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 ...
In Python, how do you convert seconds since epoch to a `datetime` object?
...datetime.utcfromtimestamp creates a naive timestamp. I had to import pytz and use datetime.fromtimestamp(1423524051, pytz.utc) to create an aware datetime.
– Matt
Feb 9 '15 at 23:21
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PHP code to remove everything but numbers
...9]/', '', '604-619-5135');
preg_replace uses PCREs which generally start and end with a /.
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Command to list all files in a folder as well as sub-folders in windows
I tried searching for a command that could list all the file in a directory as well as subfolders using a command prompt command.
I have read the help for "dir" command but coudn't find what I was looking for.
Please help me what command could get this.
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Delete last char of string
I am retrieving a lot of information in a list, linked to a database and I want to create a string of groups, for someone who is connected to the website.
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Explicitly calling a default method in Java
...ing
A.super.foo();
This could be used as follows (assuming interfaces A and C both have default methods foo())
public class ChildClass implements A, C {
@Override
public void foo() {
//you could completely override the default implementations
doSomethingElse();
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What are good message queue options for nodejs? [closed]
...appropriate. The goal is to push notifications to clients based on backend and other client actions with socketio. I could do this with just socketio but I thought maybe a proper message queue would make this cleaner and I wouldn't have to reinvent the wheel.
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How to link to part of the same document in Markdown?
I am writing a large Markdown document and would like to place a table of contents of sorts at the beginning that will provide links to various locations in the document. How can I do this?
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How to make a smooth image rotation in Android?
...imation to rotate an image that I'm using as a custom cyclical spinner in Android. Here's my rotate_indefinitely.xml file, which I placed in res/anim/ :
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