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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...
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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...
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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...
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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...
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Argparse optional positional arguments?

I have a script which is meant to be used like this: usage: installer.py dir [-h] [-v] 3 Answers ...
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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...
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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(...
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Dynamic Anonymous type in Razor causes RuntimeBinderException

... at the beginning of the referenced blog post – Simon_Weaver Feb 6 '13 at 11:54 @Simon_Weaver But the post update does...
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How does interfaces with construct signatures work?

...]; Now, how would I go about creating instances from those? say in a loop: _.each(objs, (x) => makeObj(x)? This will throw an error since x is of type ComesFromString and doesn't have a constructor. – jmlopez Aug 20 '16 at 17:40 ...
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error: Unable to find vcvarsall.bat

I tried to install the Python package dulwich : 42 Answers 42 ...