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When do I really need to use atomic instead of bool? [duplicate]
... larger concept with wider ramifications (e.g. restrictions on compiler re-ordering). Furthermore, some operations (like negation) are overloaded on the atomic operation to create a distinctly different instruction on the hardware than the native, non-atomic read-modify-write sequence of a non-atomi...
How to print SQL statement in codeigniter model
...
To display the query string:
print_r($this->db->last_query());
To display the query result:
print_r($query);
The Profiler Class will display benchmark results, queries you have run, and $_POST data at the bottom of your pages.
To enable the p...
Basic http file downloading and saving to disk in python?
...URLopener is deprecated.
And when used you will get error as below:
url_opener = urllib.URLopener() AttributeError: module 'urllib' has no
attribute 'URLopener'
So, try:
import urllib.request
urllib.request.urlretrieve(url, filename)
...
Print current call stack from a method in Python code
...port traceback
def f():
g()
def g():
for line in traceback.format_stack():
print(line.strip())
f()
# Prints:
# File "so-stack.py", line 10, in <module>
# f()
# File "so-stack.py", line 4, in f
# g()
# File "so-stack.py", line 7, in g
# for line in traceback.form...
Update MongoDB field using value of another field
...; {
requests.push( {
'updateOne': {
'filter': { '_id': document._id },
'update': { '$set': { 'name': document.name } }
}
});
if (requests.length === 500) {
//Execute per 500 operations and re-init
db.collection.bulkWrite(requests)...
What are the details of “Objective-C Literals” mentioned in the Xcode 4.4 release notes?
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This part is new. Expression Literals
When you have an expression (M_PI / 16 for example) you should put it inside parenthesis.
This syntax works for numeral expressions, booleans, finding an index in a (C-) string, boolean values, enum constants, and even character strings!
NSNumber *piO...
How to create correct JSONArray in Java using JSONObject
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@ArnoldBrown In order to add an array to mainObj it has to have a key.
– Grammin
Oct 24 '19 at 22:04
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What is the use of having destructor as private?
...e connection being open or a file being written. You could have a "request_delete" method in the class or the manager that will check that condition and it will either delete or decline, and return a status telling you what it did. That's far more flexible that just calling "delete".
...
How to initialize std::vector from C-style array?
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Don't forget that you can treat pointers as iterators:
w_.assign(w, w + len);
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How do I raise the same Exception with a custom message in Python?
...Note that you can add whatever you like to err. For example err.problematic_array=[1,2,3].
Edit: @Ducan points in a comment the above does not work with python 3 since .message is not a member of ValueError. Instead you could use this (valid python 2.6 or later or 3.x):
try:
try:
raise...