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Rails: where does the infamous “current_user” come from?
...ser_id])
end
end
This assumes that the User class exists, e.g. #{Rails.root}/app/models/user.rb.
Updated: avoid additional database queries when there is no current user.
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Python hashable dicts
...n algol-like language (as apposed to the syntax free lisp dialects you normally find them in). Because of this, different passes through the input might see different grammars, so cached parse results are invalid, unless I also store the current version of the grammar along with the cached parse re...
SQL SELECT WHERE field contains words
...%'
OR column1 LIKE '%word2%'
OR column1 LIKE '%word3%'
If you need all words to be present, use this:
SELECT * FROM mytable
WHERE column1 LIKE '%word1%'
AND column1 LIKE '%word2%'
AND column1 LIKE '%word3%'
If you want something faster, you need to look into full text search, and this...
Python dictionary from an object's fields
...a dictionary from an arbitrary object, it's sufficient to use __dict__. Usually, you'll declare your methods at class level and your attributes at instance level, so __dict__ should be fine. For example:
>>> class A(object):
... def __init__(self):
... self.b = 1
... self.c = 2
....
How to use git bisect?
...
Make sure you're at the root of your git repo, or you'll get a weird "You need to run this command from the toplevel of the working tree." error.
– Paul Whitehead
Aug 24 '17 at 8:59
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How to create module-wide variables in Python? [duplicate]
...
Here is what is going on.
First, the only global variables Python really has are module-scoped variables. You cannot make a variable that is truly global; all you can do is make a variable in a particular scope. (If you make a variable inside the Python interpreter, and then import other mo...
Java8: Why is it forbidden to define a default method for a method from java.lang.Object
...s obvious example, there are not many other good examples to be found. At root, AbstractList is designed for single inheritance. But interfaces must be designed for multiple inheritance.
Further, imagine you are writing this class:
class Foo implements com.libraryA.Bar, com.libraryB.Moo {
...
Detect & Record Audio in Python
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Great example! Really useful when I tried to wrap my head around how to record voice using Python. One quick question I had is whether there is a way to define the time period of the recording. Now it records a word? Can I play with it and ha...
What are inline namespaces for?
C++11 allows inline namespace s, all members of which are also automatically in the enclosing namespace . I cannot think of any useful application of this -- can somebody please give a brief, succinct example of a situation where an inline namespace is needed and where it is the most idiomatic s...
When to use the different log levels
...ow only warnings and errors may give quick insight into early hints at the root cause of a subsequent error. Warnings should be used sparingly so that they don't become meaningless. For example, loss of network access should be a warning or even an error in a server application, but might be just ...