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How to set the prototype of a JavaScript object that has already been instantiated?
...have an object foo in my JavaScript code. foo is a complex object and it is generated somewhere else. How can I change the prototype of the foo object?
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How to check whether a string is Base64 encoded or not
I want to decode a Base64 encoded string, then store it in my database. If the input is not Base64 encoded, I need to throw an error.
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What is the difference between == and Equals() for primitives in C#?
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Short answer:
Equality is complicated.
Detailed answer:
Primitives types override the base object.Equals(object) and return true if the boxed object is of the same type and value. (Note that it will also work for nullable types; non-null nullab...
Detecting an undefined object property
...ty, and will therefore return undefined by default when you try and access it:
if(!o.hasOwnProperty('myProperty')) {
alert("myProperty does not exist");
}
To check if the value associated with an identifier is the special value undefined, or if that identifier has not been declared. Note: this ...
Does assignment with a comma work?
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There's a lot going on here, but basically, it comes down to the comma operator.
The comma operator evaluates both of its operands (from left to right) and returns the value of the second operand.
This code:
aaa = 1,2,3
Is equivalent to:
aaa = 1;
2;
3;
So...
Why does flowing off the end of a non-void function without returning a value not produce a compiler
...e rationale includes that checking if every code path returns a value is quite difficult, and a return value could be set with embedded assembler or other tricky methods.
From C++11 draft:
§ 6.6.3/2
Flowing off the end of a function [...] results in undefined behavior in a value-returning fun...
notifyDataSetChanged example
...Application the notifyDataSetChanged() method for an ArrayAdapter but it doesn't work for me.
5 Answers
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What does $.when.apply($, someArray) do?
...and Promises and keep coming across $.when.apply($, someArray) . I'm a little unclear on what this does exactly, looking for an explanation that one line works exactly (not the entire code snippet). Here's some context:
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When do you use Java's @Override annotation and why?
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Use it every time you override a method for two benefits. Do it so that you can take advantage of the compiler checking to make sure you actually are overriding a method when you think you are. This way, if you make a common mi...
What is the difference between a function expression vs declaration in JavaScript? [duplicate]
...hes that line of code.
So if you try to call a function expression before it's loaded, you'll get an error! If you call a function declaration instead, it'll always work, because no code can be called until all declarations are loaded.
Example: Function Expression
alert(foo()); // ERROR! foo was...