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Declaring variables inside or outside of a loop
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The scope of local variables should always be the smallest possible.
In your example I presume str is not used outside of the while loop, otherwise you would not be asking the question, because declaring it inside the while loop would not be an option, since it would not comp...
Difference between java.lang.RuntimeException and java.lang.Exception
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Generally RuntimeExceptions are exceptions that can be prevented programmatically. E.g NullPointerException, ArrayIndexOutOfBoundException. If you check for null before calling any method, NullPointerException would never occur. ...
How can you encode a string to Base64 in JavaScript?
... in 8 bits, it will probably break. This isn’t a problem if you’re actually treating the string as a byte array, but if you’re trying to do something else then you’ll have to encode it first.
atob() returns a “string” where each character represents an 8-bit byte – that is, its value w...
String concatenation in Ruby
...ficient in term of memory/speed from what I've seen (not measured though). All three methods will throw an uninitialized constant error when ROOT_DIR is nil.
When dealing with pathnames, you may want to use File.join to avoid messing up with pathname separator.
In the end, it is a matter of taste....
#define macro for debug printing in C?
.... } while (0) idiom ensures that the code acts like a statement (function call). The unconditional use of the code ensures that the compiler always checks that your debug code is valid — but the optimizer will remove the code when DEBUG is 0.
If you want to work with #ifdef DEBUG, then change th...
unique object identifier in javascript
...niqueId());
Take care to make sure that whatever member you use to internally store the unique ID doesn't collide with another automatically created member name.
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How to get JS variable to retain value after page refresh? [duplicate]
...e, but this can be overcome by using JSON.stringify and JSON.parse. Technically, whenever you call .setItem(), it will call .toString() on the value and store that.
MDN's DOM storage guide (linked below), has workarounds/polyfills, that end up falling back to stuff like cookies, if localStorage isn...
how to delete all cookies of my website in php
I'm wondering if I can delete all my website's cookies when a user click on logout, because I used this as function to delete cookies but it isn't work properly:
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How do I get the number of elements in a list?
...turns 3.
Explanation
Everything in Python is an object, including lists. All objects have a header of some sort in the C implementation.
Lists and other similar builtin objects with a "size" in Python, in particular, have an attribute called ob_size, where the number of elements in the object is...
Advantages of stateless programming?
I've recently been learning about functional programming (specifically Haskell, but I've gone through tutorials on Lisp and Erlang as well). While I found the concepts very enlightening, I still don't see the practical side of the "no side effects" concept. What are the practical advantages of it? ...