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Does java.util.List.isEmpty() check if the list itself is null? [duplicate]
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You're trying to call the isEmpty() method on a null reference (as List test = null;
). This will surely throw a NullPointerException. You should do if(test!=null) instead (Checking for null first).
The method isEmpty() returns true, if an ArrayList object co...
Removing multiple keys from a dictionary safely
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How to use JavaScript regex over multiple lines?
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[.\n] does not work because . has no special meaning inside of [], it just means a literal .. (.|\n) would be a way to specify "any character, including a newline". If you want to match all newlines, you would need to add \r as well to include Windows and classic Mac OS...
Javascript AES encryption [closed]
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JSAES is a powerful implementation of AES in JavaScript.
http://point-at-infinity.org/jsaes/
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What is a monad?
...seful for.
They are a pattern for chaining operations. It looks a bit like method chaining in object-oriented languages, but the mechanism is slightly different.
The pattern is mostly used in functional languages (especial Haskell uses them pervasively) but can be used in any language which support ...
Add a prefix to all Flask routes
...operly sub-mounting your app
If you are not sure what the first paragraph means, take a look at this example application with Flask mounted inside of it:
from flask import Flask, url_for
from werkzeug.serving import run_simple
from werkzeug.wsgi import DispatcherMiddleware
app = Flask(__name__)
a...
Can you grab or delete between parentheses in vi/vim?
... flag.
By default, "item" includes brackets, braces, parens, C-style comments and various precompiler statements (#ifdef, etc.).
There is a plugin for "extended % matching" that you can find on the Vim homepage.
You can read the documentation on % and related motion commands by entering :help v...
Pure virtual function with implementation
My basic understanding is that there is no implementation for a pure virtual function, however, I was told there might be implementation for pure virtual function.
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How do I check if a number evaluates to infinity?
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@Eli: The global Infinity property isn't read-only which means that it can be redefined: For example, var x = 42; Infinity = 42; alert(x === Infinity); displays "true". (Admittedly that's an obscure case, and anyone who decides to redefine Infinity, NaN etc should expect odd things...
Test for equality among all elements of a single vector
I'm trying to test whether all elements of a vector are equal to one another. The solutions I have come up with seem somewhat roundabout, both involving checking length() .
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