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How to take all but the last element in a sequence using LINQ?
... using generators (yield return).
public static IEnumerable<T> TakeAllButLast<T>(this IEnumerable<T> source) {
var it = source.GetEnumerator();
bool hasRemainingItems = false;
bool isFirst = true;
T item = default(T);
do {
hasRemainingItems = it.MoveN...
CGridCellNumeric - A numeric cell class for the MFC Grid - C/C++ - 清...
...t of the cell.
Input validation is done on the fly as the user is typing. All validation is done in the EN_UPDATE message handler, so any cut/copy and paste operations are immediately validated. If the user deletes the text in the cell, the value is set to zero.
Using the CGridCellNumeri...
Who architected / designed C++'s IOStreams, and would it still be considered well-designed by today'
... sign of quality design.
IOStreams have a checkered history. They are actually a reworking of an earlier streams library, but were authored at a time when many of today's C++ idioms didn't exist, so the designers didn't have the benefit of hindsight. One issue that only became apparent over time wa...
Add list to set?
...rticle. Pythons hashing algorithms are explained on effbot.org and pythons __hash__ function in the python reference.
Some facts:
Set elements as well as dictionary keys have to be hashable
Some unhashable datatypes:
list: use tuple instead
set: use frozenset instead
dict: has no official count...
Argparse optional positional arguments?
I have a script which is meant to be used like this:
usage: installer.py dir [-h] [-v]
3 Answers
...
How to find encoding of a file via script on Linux?
I need to find the encoding of all files that are placed in a directory. Is there a way to find the encoding used?
17 Answe...
Transpose a data frame
...You'd better not transpose the data.frame while the name column is in it - all numeric values will then be turned into strings!
Here's a solution that keeps numbers as numbers:
# first remember the names
n <- df.aree$name
# transpose all but the first column (name)
df.aree <- as.data.frame(...
Is there a performance difference between a for loop and a for-each loop?
... iterator or index variable
completely. The resulting idiom
applies equally to collections and
arrays:
// The preferred idiom for iterating over collections and arrays
for (Element e : elements) {
doSomething(e);
}
When you see the colon (:), read it as
“in.” Thus, the loop ab...
Returning 'IList' vs 'ICollection' vs 'Collection'
...
Generally you should return a type that is as general as possible, i.e. one that knows just enough of the returned data that the consumer needs to use. That way you have greater freedom to change the implementation of the API, wit...
error: Unable to find vcvarsall.bat
I tried to install the Python package dulwich :
42 Answers
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