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Is it a good practice to use an empty URL for a HTML form's action attribute? (action=“”)
...for compatibility with legacy content. [RFC3986]
This definitely works in all current browsers, but may not work as expected in some older browsers ("browsers do weird things with an empty action="" attribute"), which is why the spec strongly discourages authors from leaving it empty:
The action a...
When saving, how can you check if a field has changed?
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Essentially, you want to override the __init__ method of models.Model so that you keep a copy of the original value. This makes it so that you don't have to do another DB lookup (which is always a good thing).
class Person(models.Model):
name = models.CharF...
Run a Docker image as a container
...s something to run. You could replace that with a program that you've installed. /bin/bash is just a handy shell that's already installed.
– Ryan Shillington
Feb 9 '17 at 15:11
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Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...an work around it from within psql by executing the DDL statement conditionally:
SELECT 'CREATE DATABASE mydb'
WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'mydb')\gexec
The manual:
\gexec
Sends the current query buffer to the server, then treats each column of each row of the query's...
How to make Eclipse behave well in the Windows 7 taskbar?
All other apps that can be pinned to the taskbar behave well.
But Eclipse doesn't show recently open projects when I right click it.
It also doesn't allow to pin some projects inside it.
Note that I have the JS version of Eclipse Helios. Which spawns a new and different taskbar icon after loading.
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How to enumerate an enum with String type?
...h Xcode 10), just add protocol conformance to CaseIterable to benefit from allCases. To add this protocol conformance, you simply need to write somewhere:
extension Suit: CaseIterable {}
If the enum is your own, you may specify the conformance directly in the declaration:
enum Suit: String, CaseIte...
Post-install script with Python setuptools
...from setuptools.command.install import install
from subprocess import check_call
class PreDevelopCommand(develop):
"""Pre-installation for development mode."""
def run(self):
check_call("apt-get install this-package".split())
develop.run(self)
class PreInstallCommand(insta...
Do you need text/javascript specified in your tags?
...tribute is optional. Since Netscape 2, the default programming language in all browsers has been JavaScript. In XHTML, this attribute is required and unnecessary. In HTML, it is better to leave it out. The browser knows what to do.
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How to reload a clojure file in REPL
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:reload-all should also work. The OP specifically says it doesn't, but I think there was something else wrong in the OP's dev environment because for a single file the two (:reload and :reload-all) should have the same effect. Here'...
What does = +_ mean in JavaScript
I was wondering what the = +_ operator means in JavaScript. It looks like it does assignments.
12 Answers
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