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Is a statically-typed full Lisp variant possible?
Is a statically-typed full Lisp variant possible? Does it even make sense for something like this to exist? I believe one of a Lisp language's virtues is the simplicity of its definition. Would static typing compromise this core principle?
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Remove Elements from a HashSet while Iterating [duplicate]
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You can manually iterate over the elements of the set:
Iterator<Integer> iterator = set.iterator();
while (iterator.hasNext()) {
Integer element = iterator.next();
if (element % 2 == 0) {
iterator.remove();
}
}...
Is using Random and OrderBy a good shuffle algorithm?
...asy to implement an O(n) shuffle. The code in the question "works" by basically giving a random (hopefully unique!) number to each element, then ordering the elements according to that number.
I prefer Durstenfield's variant of the Fisher-Yates shuffle which swaps elements.
Implementing a simple S...
How can I run PowerShell with the .NET 4 runtime?
... that will change the .NET framework loaded systemwide, which will in turn allow PowerShell to use .NET 4.0 classes:
reg add hklm\software\microsoft\.netframework /v OnlyUseLatestCLR /t REG_DWORD /d 1
reg add hklm\software\wow6432node\microsoft\.netframework /v OnlyUseLatestCLR /t REG_DWORD /d 1
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Get all table names of a particular database by SQL query?
... Server and MySQL 2) INFORMATION_SCHEMA.TABLES exists only in MySQL 3) I really wonder how comes you got so many upvotes for this ...
– Apostolos
Dec 14 '18 at 11:04
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How do I put two increment statements in a C++ 'for' loop?
...us:
for(int i = 0; i != 5; ++i,++j)
do_something(i,j);
But is it really a comma operator?
Now having wrote that, a commenter suggested it was actually some special syntactic sugar in the for statement, and not a comma operator at all. I checked that in GCC as follows:
int i=0;
int a=5;
int...
Never seen before C++ for loop
...#. In my opinion it is clearer, less of a trap for new programmers, and equally efficient.
As others have pointed out -- but to make my answer complete -- to make it work in C# you would need to change while(u--) to while(u-- != 0).
... or while(u-- >0) just in case u starts off negative. (OK, ...
What is an “unwrapped value” in Swift?
...st, you have to understand what an Optional type is. An optional type basically means that the variable can be nil.
Example:
var canBeNil : Int? = 4
canBeNil = nil
The question mark indicates the fact that canBeNil can be nil.
This would not work:
var cantBeNil : Int = 4
cantBeNil = nil // can...
What does |= (single pipe equal) and &=(single ampersand equal) mean
...icit cast, and the target variable is only evaluated once, but that's basically the gist of it.
In terms of the non-compound operators, & is a bitwise "AND" and | is a bitwise "OR".
EDIT: In this case you want Folder.Attributes &= ~FileAttributes.System. To understand why:
~FileAttribute...
Hide grid row in WPF
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UpVoted - Converters permit all this to be declarative in Xaml. I generally hate using code-behind to fiddle with visual stuff.
– Allen
May 22 '14 at 13:43
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