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Java List.add() UnsupportedOperationException
...cts to a List<String> instance but it throws an UnsupportedOperationException .
Does anyone know why?
7 Answers
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Should arrays be used in C++?
...ack C++11 support however. You will have to decide when it's better to use one rather than the other given the lack of std::array
– Nowayz
May 25 '12 at 9:59
4
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Check if a variable is a string in JavaScript
...to use and easier to read.
Either function will handle the case DRAX mentioned... that is, they both check if (A) the variable is a string literal or (B) it's an instance of the String object. In either case, these functions correctly identify the value as being a string.
lodash / Underscore.js
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Unix command to find lines common in two files
...command which could print the common lines from two or more files, does anyone know its name? It was much simpler than diff .
...
What is the best way to test for an empty string in Go?
...taste and about clarity.
Russ Cox writes in a golang-nuts thread:
The one that makes the code clear.
If I'm about to look at element x I typically write
len(s) > x, even for x == 0, but if I care about
"is it this specific string" I tend to write s == "".
It's reasonable to assu...
SAML vs federated login with OAuth
...more about delegating access to something. You are basically allowing someone to "act" as you. Its most commonly used to grant access api's that can do something on your behalf.
They are two completely different things.
Some examples that might help out.
OAuth think of an twitter. Lets say y...
Why does ConcurrentHashMap prevent null keys and values?
... barely tolerable in non-concurrent maps can't be
accommodated. The main one is that if map.get(key) returns null, you
can't detect whether the key explicitly maps to null vs the key isn't
mapped. In a non-concurrent map, you can check this via
map.contains(key), but in a concurrent one, the...
If strings are immutable in .NET, then why does Substring take O(n) time?
... not persistent"?
Because when you look at operations that are typically done on strings in .NET programs, it is in every relevant way hardly worse at all to simply make an entirely new string. The expense and difficulty of building a complex persistent data structure doesn't pay for itself.
Peopl...
How to loop through a plain JavaScript object with the objects as members?
...an't use it in the promise' then-function. You var in the loop exists only one time, so it has in every then-function the same, even the last value. If you have that problem, try "Object.keys(obj).forEach" or my answer below.
– Biber
Nov 22 '16 at 21:15
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What should my Objective-C singleton look like? [closed]
...ation:
The runtime sends initialize to each class in a program exactly one time just before the class, or any class that inherits from it, is sent its first message from within the program. (Thus the method may never be invoked if the class is not used.) The runtime sends the initialize message ...