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How to declare a type as nullable in TypeScript?
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All fields in JavaScript (and in TypeScript) can have the value null or undefined.
You can make the field optional which is different from nullable.
interface Employee1 {
name: string;
salary: number;
}
var a: Empl...
How can I add a column that doesn't allow nulls in a Postgresql database?
... postgres doc offline by doing man ALTER_TABLE :)
– allan.simon
Oct 18 '15 at 19:49
@allan.simon I've never used Post...
JavaScript code to stop form submission
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Just use a simple button instead of a submit button. And call a JavaScript function to handle form submit:
<input type="button" name="submit" value="submit" onclick="submit_form();"/>
Function within a script tag:
function submit_form() {
if (conditions) {
docu...
Is there a built-in function to print all the current properties and values of an object?
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You are really mixing together two different things.
Use dir(), vars() or the inspect module to get what you are interested in (I use __builtins__ as an example; you can use any object instead).
>>> l = dir(__builtins__)
>...
How do I use Wget to download all images into a single folder, from a URL?
I am using wget to download all images from a website and it works fine but it stores the original hierarchy of the site with all the subfolders and so the images are dotted around. Is there a way so that it will just download all the images into a single folder? The syntax I'm using at the moment i...
How do I turn a C# object into a JSON string in .NET?
...o System.Web.Extensions, you must have ASP.NET AJAX 1.0 or ASP.NET 3.5 installed on your system. Please see this stackoverflow.com/questions/7723489/…
– Sisir
Oct 15 '18 at 9:18
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Joining two lists together
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No one's really gone into when to use which method. AddRange edits a list in place, adding the second list to it (as if you called .Add(foo) a bunch of times). The Concat and Union extension methods don't change the original list. They ...
How do you do a simple “chmod +x” from within python?
... non-pythonic answer that may be a little more readable: subprocess.check_call(['chmod', '+x', 'somefile']) and let's you more easily do operations like a+rx.
– Trevor Boyd Smith
Aug 6 at 15:28
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Why aren't superclass __init__ methods automatically invoked?
...thon designers decide that subclasses' __init__() methods don't automatically call the __init__() methods of their superclasses, as in some other languages? Is the Pythonic and recommended idiom really like the following?
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How to get the HTML for a DOM element in javascript
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Now that it's 2013, calling "domnode.outerHTML" works on all major browsers (FF since v11)
– Kevin
Oct 31 '13 at 17:23
ad...