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What is the volatile keyword useful for?
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volatile has semantics for memory visibility. Basically, the value of a volatile field becomes visible to all readers (other threads in particular) after a write operation completes on it. Without volatile, readers could see some non-updated value.
To answer your question: Y...
Python: Best way to add to sys.path relative to the current running script
...o have a library located in project/lib and want the scripts to automatically load it. This is what I normally use at the top of each script:
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putting current class as return type annotation [duplicate]
...e. Instead, they are preserved in __annotations__ in string form. This is called Postponed Evaluation of Annotations, introduced in PEP 563.
Also note:
Deprecation policy
Starting with Python 3.7, a __future__ import is required to use the
described functionality. No warnings are raised...
Writing unit tests in Python: How do I start? [closed]
.... It is standard which means that it's kind of guaranteed to work well. Finally, anyone who uses your code doesn't need to install extra packages.
– Jeyekomon
Jul 6 '18 at 15:04
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Safe characters for friendly url [closed]
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To quote section 2.3 of RFC 3986:
"Characters that are allowed in a URI but do not have a reserved
purpose are called unreserved. These include uppercase and lowercase
letters, decimal digits, hyphen, period, underscore, and tilde."
ALPHA DIGIT "-" / "." / "_" / "~"
N...
Objective-C categories in static library
...roject as direct dependency (target -> general -> direct dependencies) and all works OK, but categories. A category defined in static library is not working in app.
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Rename multiple files in a directory in Python [duplicate]
...e script itself. Instead of using . as the dir, you could make a variable called dir and use that, then prepend dir to the filename.
– styfle
May 18 '11 at 5:53
18
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Flask-SQLalchemy update a row's information
...e many objects to be updated.
If you want to give add_user permission to all the admins,
rows_changed = User.query.filter_by(role='admin').update(dict(permission='add_user'))
db.session.commit()
Notice that filter_by takes keyword arguments (use only one =) as opposed to filter which takes an e...
M_PI works with math.h but not with cmath in Visual Studio
...) and suddenly it compile perfectly.
Try moving it higher up the page. Totally unsure as to why this would cause issues though.
Edit: Figured it out. The #include <math.h> occurs within cmath's header guards. This means that something higher up the list of #includes is including cmath with...
Python: Tuples/dictionaries as keys, select, sort
...es and so on.
I'd like to organize them in a data structure in Python that allows for easy selection and sorting. My idea was to put them into a dictionary with tuples as keys, e.g.,
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