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Preserving order with LINQ
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Actually, I think Distinct preserves original (first found) order - so {1,2,1,3,1,3,4,1,5} would be {1,2,3,4,5}
– Marc Gravell♦
Oct 15 '08 at 14:33
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How to filter a dictionary according to an arbitrary condition function?
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And here is a good explanation why the function call dict() is slower than the constructor/literal syntax {} doughellmann.com/2012/11/…
– dorvak
Jul 10 '13 at 9:37
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How efficient is locking an unlocked mutex? What is the cost of a mutex?
... access to the object happens often, then multiple locks would increase parallelism. At the cost of maintainability, since more locking means more debugging of the locking.
How efficient is it to lock a mutex? I.e. how much assembler instructions are there likely and how much time do they take (...
How do I check if a string is unicode or ascii?
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In Python 3, all strings are sequences of Unicode characters. There is a bytes type that holds raw bytes.
In Python 2, a string may be of type str or of type unicode. You can tell which using code something like this:
def whatisthis(s):...
Environment variables for java installation
...r-unique-entries does not contain any other references to another Java installation folder.
Note for Windows users on 64-bit systems:
Progra~1 = 'Program Files'
Progra~2 = 'Program Files(x86)'
Notice that these environment variables are derived from the "root" environment variable JAVA_HOME...
How do you convert a DataTable into a generic list?
...e DataTableExtensions.AsEnumerable (an extension method) and then if you really need a List<DataRow> instead of just IEnumerable<DataRow> you can call Enumerable.ToList:
IEnumerable<DataRow> sequence = dt.AsEnumerable();
or
using System.Linq;
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List<DataRow> list = dt.A...
What is the relative performance difference of if/else versus switch statement in Java?
...ic interface Action {
void execute(String input);
}
And get hold of all implementations in some Map. You can do this either statically or dynamically:
Map<String, Action> actions = new HashMap<String, Action>();
Finally replace the if/else or switch by something like this (leav...
Cooler ASCII Spinners? [closed]
... even in random order http://www.fileformat.info/info/unicode/block/braille_patterns/images.htm
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Bash empty array expansion with `set -u`
...ad. Other patterns, such as ${arr[@]-} or ${arr[@]:0}, are not safe across all major versions of Bash.
As the table below shows, the only expansion that is reliable across all modern-ish Bash versions is ${arr[@]+"${arr[@]}"} (column +"). Of note, several other expansions fail in Bash 4.2, includin...
Check a radio button with javascript
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Technically it's CSS selector syntax. jQuery just borrowed and extended it
– Tim Seguine
Jan 16 '14 at 16:10
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