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Apply function to all elements of collection through LINQ [duplicate]
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@BKSpurgeon: Select is a projection: 1) it's lazily evaluated; just calling it won't do anything. 2) Select produces a result - ForEach doesn't.
– Jon Skeet
Mar 20 '17 at 9:24
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How different is Objective-C from C++? [closed]
...that can be done at compile time. For example, using a variant type(like a union) the compiler can enforce that all cases are written or handled. So you don't forget about handling the edge cases of a problem. However, all these checks come at a price when compiling. Obj-C is much faster at compilin...
What is “android.R.layout.simple_list_item_1”?
...r the individual rows. There are others with checkedtextviews for multiple selections, you can make custom layouts that include images, and multiple textviews for example. These android.R ones are just some easy to use, already created resources for you.
– Kevin Coppock
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Is Mono ready for prime time? [closed]
...e experience than using the GUI, which is a very "unorthodox" state of the union for Linux environments...
Once/During getting your stuff actually BUILT, you might see some wildernesses even for code that SHOULD be supported like:
the compiler getting borked on certain constructs
and certain mo...
C++ preprocessor __VA_ARGS__ number of arguments
...VA_ARGS__), __VA_ARGS__))
void sum(int numargs, ...);
int main(int argc, char *argv[]) {
SUM(1);
SUM(1, 2);
SUM(1, 2, 3);
SUM(1, 2, 3, 4);
return 1;
}
void sum(int numargs, ...) {
int total = 0;
va_list ap;
printf("sum() called with %d params:", numargs);
...
Is “else if” a single keyword?
...s section on keywords.
The grammar in section 6.4 also makes this clear:
selection-statement:
if ( condition ) statement
if ( condition ) statement else statement
The if in else if is a statement following the else term. The section also says:
[...]The substatement in a selection-statement...
Inheriting from a template class in c++
... create objects from any other class). Another such class would be Area<char>. Note that those are completely different classes, which have nothing in common except for the fact that they were generated from the same class template.
Since Area is not a class, you cannot derive the class Recta...
Only read selected columns
...from the data.table-package:
You can specify the desired columns with the select parameter from fread from the data.table package. You can specify the columns with a vector of column names or column numbers.
For the example dataset:
library(data.table)
dat <- fread("data.txt", select = c("Year...
How to get the error message from the error code returned by GetLastError()?
...dated (11/2017) to take into consideration some comments.
Easy example:
wchar_t buf[256];
FormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
NULL, GetLastError(), MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
buf, (sizeof(buf) / sizeof(wchar_t)),...
Best way to parseDouble with comma as decimal separator?
... The problem with NumberFormat is that it will silently ignore invalid characters. So if you try to parse "1,23abc" it will happily return 1.23 without indicating to you that the passed-in String contained non-parsable characters. In some situations that might actually be desirable, but I don't ...