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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.
...
Detecting when the 'back' button is pressed on a navbar
...to work under certain scenarios in iOS 8+. I can't verify that that is actually the case without further details.
For those of you however in that situation there's an alternative. Detecting when a view controller is being popped is possible by overriding willMove(toParentViewController:). The basi...
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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Understand the “Decorator Pattern” with a real world example
...
Decorator pattern achieves a single objective of dynamically adding
responsibilities to any object.
Consider a case of a pizza shop. In the pizza shop they will sell few pizza varieties and they will also provide toppings in the menu. Now imagine a situation wherein if the piz...