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Objective-C ARC: strong vs retain and weak vs assign
There are two new memory management attributes for properties introduced by ARC, strong and weak .
8 Answers
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mongodb count num of distinct values per field/key
Is there a query for calculating how many distinct values a field contains in DB.
5 Answers
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Where is a complete example of logging.config.dictConfig?
...G_CONFIG = {
'version': 1,
'disable_existing_loggers': True,
'formatters': {
'standard': {
'format': '%(asctime)s [%(levelname)s] %(name)s: %(message)s'
},
},
'handlers': {
'default': {
'level': 'INFO',
'formatter':...
Downloading Java JDK on Linux via wget is shown license page instead
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*Works as of 07-11-2020 for JDK 14
wget --no-check-certificate -c --header "Cookie: oraclelicense=accept-securebackup-cookie" https://download.oracle.com/otn-pub/java/jdk/14.0.1+7/664493ef4a6946b186ff29eb326336a2/jdk-14.0.1_linux-x64_bin.rpm -O ~/Do...
What is an alternative to execfile in Python 3?
...y idea why they would do such a thing? This is so much more verbose than before. Also, it doesn't work for me on Python3.3. I get "No such file or directory" when I exec(open('./some_file').read()). I have tried including the '.py' extension and also excluding the './' as well
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clang: how to list supported target architectures?
...d clang binaries may not correspond to the same version of LLVM.
However, for the sake of argument, let's say that you compiled both LLVM and Clang yourself or that you're otherwise happy to accept your LLVM binaries as good enough:
llc --version will give a list of all architectures it supports....
What's the $unwind operator in MongoDB?
...ts, joins, etc. from your mind. The way that it stores your data is in the form of documents and collections, which allows for a dynamic means of adding and obtaining the data from your storage locations.
That being said, in order to understand the concept behind the $unwind parameter, you first mu...
Comparing mongoose _id and strings
...method, if you wish to store a stringified version of the ObjectID in JSON format, or a cookie.
If you use ObjectID = require("mongodb").ObjectID (requires the mongodb-native library) you can check if results.userId is a valid identifier with results.userId instanceof ObjectID.
Etc.
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Filter by property
...del.objects)
But it's better to use a list comprehension:
filtered = [x for x in MyModel.objects if x.myproperty()]
or even better, a generator expression:
filtered = (x for x in MyModel.objects if x.myproperty())
sha...
What is an 'endpoint' in Flask?
.../greeting/<name>')
def give_greeting(name):
return 'Hello, {0}!'.format(name)
Note that the function you referred to (add_url_rule) achieves the same goal, just without using the decorator notation. Therefore, the following is the same:
# No "route" decorator here. We will add routing u...