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Const in JavaScript: when to use it and is it necessary?
...ently come across the const keyword in JavaScript. From what I can tell, it is used to create immutable variables , and I've tested to ensure that it cannot be redefined (in Node.js):
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Long-held, incorrect programming assumptions [closed]
...g concepts (design patterns, the latest new language, computational complexity, lambda expressions, you name it).
Reading blogs, Stack Overflow and programming books always seemed to make me feel that I was behind the curve on the things that all programmers must just know intuitively.
I've reali...
Using try vs if in python
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You often hear that Python encourages EAFP style ("it's easier to ask for forgiveness than permission") over LBYL style ("look before you leap"). To me, it's a matter of efficiency and readability.
In your example (say that instead of returning a list or an empty string, the...
Using an HTML button to call a JavaScript function
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There are a few ways to handle events with HTML/DOM. There's no real right or wrong way but different ways are useful in different situations.
1: There's defining it in the HTML:
<input id="clickMe" type="button" value="clickme" onclick="doFunction();" /&g...
How to save password when using Subversion from the console
... option that I have. When I try to do any Subversion action, e.g. svn commit , it prompts for the account password every time. Is there a way to save this password somehow so that I don't have to retype it every time?
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Switch statement fall-through…should it be allowed? [closed]
For as long as I can remember I have avoided using switch statement fall-through. Actually, I can't remember it ever entering my consciousness as a possible way to do things as it was drilled into my head early on that it was nothing more than a bug in the switch statement. However, today I ran acro...
What exactly do “IB” and “UB” mean?
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IB: Implementation-defined Behaviour. The standard leaves it up to the particular compiler/platform to define the precise behaviour, but requires that it be defined.
Using implementation-defined behaviour can be useful, but makes your code less portable.
UB: Undefined Behaviour. T...
Why would I want stage before committing in Git?
I'm new to version control and I understand that "committing" is essentially creating a backup while updating the new 'current' version of what you're working on.
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Calling virtual functions inside constructors
...l of the hierarchy in the current constructor and no further.
The C++ FAQ Lite covers this in section 23.7 in pretty good detail. I suggest reading that (and the rest of the FAQ) for a followup.
Excerpt:
[...] In a constructor, the virtual call mechanism is disabled because overriding from derived...
Why is there a `null` value in JavaScript?
...ll value in JS" - there is a null value of some sort in most languages and it is generally considered very useful.
The question is, "why is there an undefined value in JS". Major places where it is used:
when you declare var x; but don't assign to it, x holds undefined;
when your function gets fe...