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Do try/catch blocks hurt performance when exceptions are not thrown?

... Check it. static public void Main(string[] args) { Stopwatch w = new Stopwatch(); double d = 0; w.Start(); for (int i = 0; i < 10000000; i++) { try { d = Math.Sin(1); } catch (Exception ex) ...
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How can I get all the request headers in Django?

...rip will strip out all leading characters that match any characters in the string you give it, so if you have a header "HTTP_TOKEN_ID" it will give back "OKEN_ID", because the "T" at the beginning of "TOKEN" matches a character in the string passed to lstrip. The way to do it is prefix = 'HTTP_'; h...
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Ruby replace string with captured regex pattern

...only seem to be interested in the capture group, note that you can index a string with a regex: "foo"[/oo/] #=> "oo" "Z_123: foobar"[/^Z_.*(?=:)/] #=> "Z_123" share | improve this answer ...
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Converting between datetime, Timestamp and datetime64

...nstruct NumPy's datetime64 and timedelta64 objects Pass an integer with a string for the units. See all units here. It gets converted to that many units after the UNIX epoch: Jan 1, 1970 >>> np.datetime64(5, 'ns') numpy.datetime64('1970-01-01T00:00:00.000000005') >>> np.datetim...
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Finding the source code for built-in Python functions?

...>> help(str) Help on class str in module __builtin__: class str(basestring) | str(object='') -> string | | Return a nice string representation of the object. | If the argument is a string, the return value is the same object. | | Method resolution order: | str | bases...
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How can I check for “undefined” in JavaScript? [duplicate]

...e undefined, then use the typeof operator, which is guaranteed to return a string: if (typeof myVar !== 'undefined') Direct comparisons against undefined are troublesome as undefined can be overwritten. window.undefined = "foo"; "foo" == undefined // true As @CMS pointed out, this has been pa...
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How to simplify a null-safe compareTo() implementation?

... Using Java 8: private static Comparator<String> nullSafeStringComparator = Comparator .nullsFirst(String::compareToIgnoreCase); private static Comparator<Metadata> metadataComparator = Comparator .comparing(Metadata::getName, nullSafeStri...
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Why does the is operator return false when given null?

... I think null is string returning false is very intuitive. Null means nothing, and it is definitely not a string. So it should return false. While it is a choice the language designers made, it is a very intuitive one when you consider the re...
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When to use ref and when it is not necessary in C#

...ltiple return values create structs'). Take for example IPAddress.TryParse(string, out IPAddress). – Swen Kooij Dec 6 '13 at 21:47 ...
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Get path of executable

...dlib> #include <algorithm> #include <iterator> #include <string> #include <vector> #include <boost/filesystem/operations.hpp> #include <boost/filesystem/path.hpp> #include <boost/predef.h> #include <boost/version.hpp> #include <boost/tokenizer.h...