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How to wait for several Futures?
...ave several futures and need to wait until either any of them fails or all of them succeed.
8 Answers
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Google Maps v3 - limit viewable area and zoom level
is it possible to limit Google map v3 to a certain area? I want to allow displaying only some area (e.g. a country) and disallow the user to slide elsewhere. Also I want to restrict the zoom level - e.g. only between levels 6 and 9. And I want to use all the base map types.
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Mongoose, Select a specific field with find
... I think .select just is a filter to choose field after you get all of that, my recommendation is to use .find({}, 'name -_id')
– hong4rc
Mar 2 '19 at 16:15
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What is an alternative to execfile in Python 3?
It seems they canceled in Python 3 all the easy way to quickly load a script by removing execfile()
12 Answers
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Why can't I see the “Report Data” window when creating reports?
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After I accidentally closed this window, I took an hour to find how to bring it back up.
The right answer is indeed:
View-->Report Data (ctrl+alt+D)
The tricky part: the 'Report Data' entry does not always appear in the 'View' dropdown...
What is Weak Head Normal Form?
... further (i.e. it contains no un-evaluated thunks).
These expressions are all in normal form:
42
(2, "hello")
\x -> (x + 1)
These expressions are not in normal form:
1 + 2 -- we could evaluate this to 3
(\x -> x + 1) 2 -- we could apply the function
"he" ++ "llo" ...
How to Update Multiple Array Elements in mongodb
...At this moment it is not possible to use the positional operator to update all items in an array. See JIRA http://jira.mongodb.org/browse/SERVER-1243
As a work around you can:
Update each item individually
(events.0.handled events.1.handled
...) or...
Read the document, do the edits
manually and ...
What is the difference between `sorted(list)` vs `list.sort()`?
...sorts the list in-place, mutating the list indices, and returns None (like all in-place operations).
sorted() works on any iterable, not just lists. Strings, tuples, dictionaries (you'll get the keys), generators, etc., returning a list containing all elements, sorted.
Use list.sort() when you wa...
How do you query for “is not null” in Mongo?
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This will return all documents with a key called "IMAGE URL", but they may still have a null value.
db.mycollection.find({"IMAGE URL":{$exists:true}});
This will return all documents with both a key called "IMAGE URL" and a non-null value.
d...
ThreadStatic v.s. ThreadLocal: is generic better than attribute?
...low is the simple demonstration:
public static ThreadLocal<int> _threadlocal =
new ThreadLocal<int>(() =>
{
return Thread.CurrentThread.ManagedThreadId;
});
public static void Main()
{
new Thread(() =>
{
...