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What does $_ mean in PowerShell?
...dItem | Add-Member -Type NoteProperty -Name Bar -Value $_.Name -PassThru | Select Bar ... Well, it can work if you have a $_ in the scope where you're executing that pipeline. But that's very different from what you usually mean when trying to write something like that.
– Joey
...
How to use sed to replace only the first occurrence in a file?
... then only looked for starting on the next line. Therefore, both lines are selected in this case, and the s/foo/bar/ substitution is performed on both of them.
sed '1,/foo/ s//bar/' <<<$'1foo\n2foo\n3foo' fails: with sed: first RE may not be empty (BSD/macOS) and sed: -e expression #1, char...
Why does Path.Combine not properly concatenate filenames that start with Path.DirectorySeparatorChar
...? "path1" : "path2");
Contract.EndContractBlock();
CheckInvalidPathChars(path1);
CheckInvalidPathChars(path2);
return CombineNoChecks(path1, path2);
}
internal static string CombineNoChecks(string path1, string path2)
{
if (path2.Length == 0)
return path1;
if (path...
__FILE__, __LINE__, and __FUNCTION__ usage in C++
...docs/papers/2019/p1208r5.pdf
The documentation says:
constexpr const char* function_name() const noexcept;
6 Returns: If this object represents a position in the body of a function,
returns an implementation-defined NTBS that should correspond to the
function name. Otherwise, returns ...
Why does appending “” to a String save memory?
...s that substring() gives a window onto an existing String - or rather, the character array underlying the original String. Hence it will consume the same memory as the original String. This can be advantageous in some circumstances, but problematic if you want to get a substring and dispose of the o...
SQLAlchemy: print the actual query
...s:
print(str(statement))
This applies both to an ORM Query as well as any select() or other statement.
Note: the following detailed answer is being maintained on the sqlalchemy documentation.
To get the statement as compiled to a specific dialect or engine, if the statement itself is not already bo...
Generate fixed length Strings filled with whitespaces
I need to produce fixed length string to generate a character position based file. The missing characters must be filled with space character.
...
Repeating characters in VIM insert mode
Is there a way of repeating a character while in Vim's insert mode? For example, say I would like to insert 80 dashes, in something like emacs I would type:
...
Difference between malloc and calloc?
...ngful. Also note that calloc doesn't necessarily do what you think for non-char types. Nobody really uses trap representations any more, or non-IEEE floats, but that's no excuse for thinking your code is truly portable when it isn't.
– Steve Jessop
Oct 8 '09 at...
How to throw an exception in C?
...);
}catch(int64_t x){
printf("good %ld",x);
}
}
int main(int argc, char *argv[])
{
foo();
return 0;
}
to compile it
gcc -o bar.o -c bar.c && g++ a.cc bar.o && ./a.out
output
good 1976
http://mentorembedded.github.io/cxx-abi/abi-eh.html has more detail info about _...