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Enum type constraints in C# [duplicate]
...an the restrictions being removed from C# 5. (I assume C# 4 is locked down now.)
– Jon Skeet
Sep 10 '09 at 8:52
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How to throw std::exceptions with variable messages?
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what's the difference between this and an std::stringstream? It appears to contain a stringstream, but has (as far as I can tell), no extra functionality.
– matts1
Sep 4 '16 at 1:43
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Can an enum class be converted to the underlying type?
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I think you can use std::underlying_type to know the underlying type, and then use cast:
#include <type_traits> //for std::underlying_type
typedef std::underlying_type<my_fields>::type utype;
utype a = static_cast<utype>(my_fields::field);
With th...
How can I efficiently select a Standard Library container in C++11?
There's a well known image (cheat sheet) called "C++ Container choice". It's a flow chart to choose the best container for the wanted usage.
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Mean per group in a data.frame [duplicate]
..."Rate2"), row.names = c(NA, -9L), class = c("data.table", "data.frame"))
Now to take the mean of Rate1 and Rate2 for all 3 months, for each person (Name):
First, decide which columns you want to take the mean of
colstoavg <- names(mydt)[3:4]
Now we use lapply to take the mean over the column...
What is the pythonic way to avoid default parameters that are empty lists?
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def my_func(working_list=None):
if working_list is None:
working_list = []
working_list.append("a")
print(working_list)
The docs say you should use None as the default and explicitly test for it in the body of the function.
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Convert a Scala list to a tuple?
...uple
t: (Int, Int, Int) = (1,2,3)
Also, you can use a wildcard operator if not sure about a size of the List
val t = x match {
case List(a, b, c, _*) => (a, b, c)
}
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Eclipse IDE: How to zoom in on text?
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It is now a official feature in Neon: eclipse.org/eclipse/news/4.6/platform.php
– gustavovelascoh
Nov 26 '16 at 1:42
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What is the Sign Off feature in Git for?
...eated the patch in question, or that you certify that to the best of your knowledge, it was created under an appropriate open-source license, or that it has been provided to you by someone else under those terms. This can help establish a chain of people who take responsibility for the copyright sta...
How to change the button text of ?
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@Ya can you tell what browser and it version? Tested now on Chrome Version 43.0.2357.130 (64-bit) on Linux and all examples works perfectly.
– Fernando Kosh
Jul 6 '15 at 21:16
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