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What are inline namespaces for?
C++11 allows inline namespace s, all members of which are also automatically in the enclosing namespace . I cannot think of any useful application of this -- can somebody please give a brief, succinct example of a situation where an inline namespace is needed and where it is the most idiomatic s...
How to select the row with the maximum value in each group
...ata.table) ## 1.9.2
group <- as.data.table(group)
If you want to keep all the entries corresponding to max values of pt within each group:
group[group[, .I[pt == max(pt)], by=Subject]$V1]
# Subject pt Event
# 1: 1 5 2
# 2: 2 17 2
# 3: 3 5 2
If you'd like ju...
Python hashable dicts
...n algol-like language (as apposed to the syntax free lisp dialects you normally find them in). Because of this, different passes through the input might see different grammars, so cached parse results are invalid, unless I also store the current version of the grammar along with the cached parse re...
SQL SELECT WHERE field contains words
...%'
OR column1 LIKE '%word2%'
OR column1 LIKE '%word3%'
If you need all words to be present, use this:
SELECT * FROM mytable
WHERE column1 LIKE '%word1%'
AND column1 LIKE '%word2%'
AND column1 LIKE '%word3%'
If you want something faster, you need to look into full text search, and this...
How do I list all files of a directory?
How can I list all files of a directory in Python and add them to a list ?
21 Answers
...
Which .NET Dependency Injection frameworks are worth looking into? [closed]
...cy injection container with support for constructor, property, and method call injection
Autofac - An addictive .NET IoC container
DryIoc - Simple, fast all fully featured IoC container.
Ninject - The ninja of .NET dependency injectors
StructureMap - The original IoC/DI Container for .Net
Spring.Net...
Understanding __get__ and __set__ and Python descriptors
...th the Temperature class). For example:
temp=Temperature()
temp.celsius #calls celsius.__get__
Accessing the property you assigned the descriptor to (celsius in the above example) calls the appropriate descriptor method.
instance in __get__ is the instance of the class (so above, __get__ would r...
Is there a way to check if WPF is currently executing in design mode or not?
... while in Visual Studio:
DesignerProperties.IsInDesignTool
Edit: And finally, in the interest of completeness, the equivalent in WinRT / Metro / Windows Store applications is DesignModeEnabled:
Windows.ApplicationModel.DesignMode.DesignModeEnabled
...
Does making a struct volatile make all its members volatile?
...er way to look at the original question):
Does making a struct const make all its members const?
If I have:
struct whatever { int data; };
const whatever test;
Will test.data be const too?
My answer is : Yes. If you declare an object of type whatever with const then all its members will be co...
Python dictionary from an object's fields
...a dictionary from an arbitrary object, it's sufficient to use __dict__. Usually, you'll declare your methods at class level and your attributes at instance level, so __dict__ should be fine. For example:
>>> class A(object):
... def __init__(self):
... self.b = 1
... self.c = 2
....