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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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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 validate an email address using a regular expression?
...me web page as was the address.
Confirmation tokens are the only way to know you got the address of the person entering it. This is why most mailing lists now use that mechanism to confirm sign-ups. After all, anybody can put down president@whitehouse.gov, and that will even parse as legal, but it...
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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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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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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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...
Mail multipart/alternative vs multipart/mixed
...ns Email that wraps this up nicely, meaning you don't need to know below.
If your requirement is an email with:
text and html versions
html version has embedded (inline) images
attachments
The only structure I found that works with Gmail/Outlook/iPad is:
mixed
alternative
text
related
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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...
Checking a Python module version at runtime
...ernative, I'd like to suggest that you don't check at run time (don't know if that's a hard requirement or not). For the python stuff I write that has external dependencies (3rd party libraries), I write a script that users can run to check their python install to see if the appropriate versions of...