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Python Dictionary Comprehension
...nsion, they create a new dictionary; you can't use them to add keys to an existing dictionary. Also, you have to specify the keys and values, although of course you can specify a dummy value if you like.
>>> d = {n: n**2 for n in range(5)}
>>> print d
{0: 0, 1: 1, 2: 4, 3: 9, 4: ...
PHP - concatenate or directly insert variables in string
...
Between those two syntaxes, you should really choose the one you prefer :-)
Personally, I would go with your second solution in such a case (Variable interpolation), which I find easier to both write and read.
The result will be the same; and eve...
Does the 'mutable' keyword have any purpose other than allowing the variable to be modified by a con
... in a way that is visible through the public interface, like your locking example. Another example would be a class that computes a value the first time it is requested, and caches the result.
Since c++11 mutable can be used on a lambda to denote that things captured by value are modifiable (they...
When is memoization automatic in GHC Haskell?
...
GHC does not memoize functions.
It does, however, compute any given expression in the code at most once per time that its surrounding lambda-expression is entered, or at most once ever if it is at top level. Determining where the lambda-expressions are can be a little tricky when you use synt...
Overriding fields or properties in subclasses
...n 1 is polymorphic.
Fields by themselves cannot be overridden. Which is exactly why Option 2 returns the new keyword warning.
The solution to the warning is not to append the “new” keyword, but to implement Option 1.
If you need your field to be polymorphic you need to wrap it in a Proper...
How can I find the length of a number?
...
var x = 1234567;
x.toString().length;
This process will also work forFloat Number and for Exponential number also.
share
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i...
Asynchronously wait for Task to complete with timeout
...t;T> to complete with some special rules:
If it hasn't completed after X milliseconds, I want to display a message to the user.
And if it hasn't completed after Y milliseconds, I want to automatically request cancellation .
...
Make WPF window draggable, no matter what element is clicked
... will allow users to drag the Window when they click/drag on any control, EXCEPT for controls which eat the MouseDown event (e.Handled = true)
You can use PreviewMouseDown instead of MouseDown, but the drag event eats the Click event, so your window stops responding to left-mouse click events. If y...
Python Pandas merge only certain columns
...t possible to only merge some columns? I have a DataFrame df1 with columns x, y, z, and df2 with columns x, a ,b, c, d, e, f, etc.
...
What is the canonical way to trim a string in Ruby without creating a new string?
...ble itself if it was stripped.
According to Ruby standards, a method suffixed with an exclamation mark changes the variable in place.
Hope this helps.
Update: This is output from irb to demonstrate:
>> @title = "abc"
=> "abc"
>> @title.strip!
=> nil
>> @title
=> "abc"
...