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Is it safe to resolve a promise multiple times?
... rejected), that is it for a defered object - it is done.
If you should call then(...) on it's promise again, you should immediately get the (first) resolved/rejected result.
Additional calls to resolve() will not (should not?) have any effect. Not sure what happens if you attempt to reject a de...
When should I use uuid.uuid1() vs. uuid.uuid4() in python?
...d4() generates, as you said, a random UUID. The chance of a collision is really, really, really small. Small enough, that you shouldn't worry about it. The problem is, that a bad random-number generator makes it more likely to have collisions.
This excellent answer by Bob Aman sums it up nicely. (I...
Python: finding an element in a list [duplicate]
...hod .index.
For the objects in the list, you can do something like:
def __eq__(self, other):
return self.Value == other.Value
with any special processing you need.
You can also use a for/in statement with enumerate(arr)
Example of finding the index of an item that has value > 100.
for...
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" ...
Determine if Android app is being used for the first time
...
Beware for Android 6.0 (API 23 - Marshmallow) or above auto backup (developer.android.com/guide/topics/data/autobackup.html)is enabled by default. If the users uninstalls and then reinstalls the app the shared preferences will be recovered. So on reinstalls you ca...
How to export all data from table to an insertable sql format?
I have a Table (call it A_table ) in a database (call it A_db ) in Microsoft SQL Server Management Studio, and there are 10 rows.
...
How to create a drop-down list?
...iew:
XML:
<Spinner
android:id="@+id/spinner1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@android:drawable/btn_dropdown"
android:spinnerMode="dropdown"/>
Java:
//get the spinner from the xml.
Spinner dropdown = findVi...
How do you implement a class in C? [closed]
...se C (no C++ or object oriented compilers) and I don't have dynamic memory allocation, what are some techniques I can use to implement a class, or a good approximation of a class? Is it always a good idea to isolate the "class" to a separate file? Assume that we can preallocate the memory by assumin...
How to get the name of the calling method?
...eem to work in Rails 5.2.1. In Rails controller this returns "block in make_lambda". I guess this is for Ruby only.
– dcangulo
Nov 14 '18 at 4:59
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...
MongoDB, remove object from array
...
try..
db.mycollection.update(
{'_id': ObjectId("5150a1199fac0e6910000002")},
{ $pull: { "items" : { id: 23 } } },
false,
true
);
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