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Regex - Should hyphens be escaped? [duplicate]
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Correct on all fronts. Outside of a character class (that's what the "square brackets" are called) the hyphen has no special meaning, and within a character class, you can place a hyphen as the first or last character in the range (e.g....
Identify if a string is a number
...ld use double.TryParse, since we want to know if it represents a number at all.
– John Gietzen
May 21 '09 at 18:31
6
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Null coalescing in powershell
...t the Powershell versions involving functions/aliases will always evaluate all arguments. If this is a problem, use the if expression form.
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C++ Lock-free Hazard Pointer（冒险指针） - C/C++ - 清泛网 - 专注C/C++及内核技术
C++ Lock-free Hazard Pointer（冒险指针）hazard_pointer1 Safe Reclamation MethodsFolly 的 Hazard Pointer 实现中有一段注释，详细描述了 C++ 里几种主流的安全内存回收方法，列表如下：优点缺点场景Locking易用读高开销
1. Safe Reclamation Methods
Fo...
Initializing a static std::map in C++
... Every time I see something like that done with C++, I think of all the horrendous template code that must be behind it. Good example!
– Greg Hewgill
Sep 26 '08 at 10:22
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Lazy Method for Reading Big File in Python?
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To write a lazy function, just use yield:
def read_in_chunks(file_object, chunk_size=1024):
"""Lazy function (generator) to read a file piece by piece.
Default chunk size: 1k."""
while True:
data = file_object.read(chunk_size)
if not data:
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SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
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Without the update-and-join notation (not all DBMS support that), use:
UPDATE QuestionTrackings
SET QuestionID = (SELECT QuestionID
FROM AnswerTrackings
WHERE AnswerTrackings.AnswerID = QuestionTrackings.AnswerID)
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Why do some C# lambda expressions compile to static methods?
...l implementation most likely varies slightly):
private class <Main>b__0
{
public int age;
public void withClosure(string s)
{
Console.WriteLine("My name is {0} and I am {1} years old", s, age)
}
}
private static class <Main>b__1
{
public static void withoutC...
Find the most common element in a list
...roups by the item only (via operator.itemgetter). The auxiliary function, called once per grouping during the max computation, receives and internally unpacks a group - a tuple with two items (item, iterable) where the iterable's items are also two-item tuples, (item, original index) [[the items of ...
Advantages to Using Private Static Methods
When creating a class that has internal private methods, usually to reduce code duplication, that don't require the use of any instance fields, are there performance or memory advantages to declaring the method as static?
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