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Why is there no xrange function in Python3?
... can use xrange from this project. There is futurize tool to automatically convert you source code: python-future.org/…
– guettli
Mar 22 '18 at 20:42
add a comment
...
ExecuteReader requires an open and available Connection. The connection's current state is Connectin
...lication
execution, many identical connections will be repeatedly opened and
closed. To minimize the cost of opening connections, ADO.NET uses an
optimization technique called connection pooling.
Connection pooling reduces the number of times that new connections
must be opened. The poo...
Python group by
...ultdict(list)
>>> for v, k in input: res[k].append(v)
...
Then, convert that dictionary into the expected format.
>>> [{'type':k, 'items':v} for k,v in res.items()]
[{'items': ['9085267', '11788544'], 'type': 'NOT'}, {'items': ['5238761', '5349618', '962142', '7795297', '7341464...
error: passing xxx as 'this' argument of xxx discards qualifiers
... {
return name;
}
This is necessary because now you can call getId() and getName() on const objects as:
void f(const StudentT & s)
{
cout << s.getId(); //now okay, but error with your versions
cout << s.getName(); //now okay, but error with your versions
}
As a s...
Reuse Cucumber steps
...thing", "fill something". The natural way would be reuse steps, instead of convert each step into a call to a function. IMO, calling steps inside steps should just be improved.
– dgmora
Jun 27 '13 at 16:28
...
Insert, on duplicate update in PostgreSQL?
...mple 38-2. Exceptions with UPDATE/INSERT
This example uses exception handling to perform either UPDATE or INSERT, as appropriate:
CREATE TABLE db (a INT PRIMARY KEY, b TEXT);
CREATE FUNCTION merge_db(key INT, data TEXT) RETURNS VOID AS
$$
BEGIN
LOOP
-- first try to update the key...
How do I combine a background-image and CSS3 gradient on the same element?
...ut images that aren't already semi-transparent can't be easily/dynamically converted to be used in this manner. That's why I find the approach of putting the gradient first more generally useful.
– waldyrious
Jan 14 '18 at 13:23
...
Create RegExps on the fly using string variables
...e commonly you want to replace all occurrences, in which case, you have to convert the string into a global (/.../g) RegExp. You can do this from a string using the new RegExp constructor:
new RegExp(string_to_replace, 'g')
The problem with this is that any regex-special characters in the string ...
What is the relationship between Looper, Handler and MessageQueue in Android?
I have checked the official Android documentation/guide for Looper , Handler and MessageQueue . But I couldn't get it. I am new to android, and got very confused with these concepts.
...
What are the differences between Rust's `String` and `str`?
...an be seen as a fixed-length String that cannot be resized (you can always convert it into a String if you want to resize it).
A very similar relationship exists between [T] and Vec<T> except there is no UTF-8 constraint and it can hold any type whose size is not dynamic.
The use of str on t...