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Reference — What does this symbol mean in PHP?
... that come up every now and then about syntax in PHP. This is also a Community Wiki, so everyone is invited to participate in maintaining this list.
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Accessing Object Memory Address
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The Python manual has this to say about id():
Return the "identity'' of an object.
This is an integer (or long integer)
which is guaranteed to be unique and
constant for this object during its
lifetime. Two objects with
non-overlapping lifetimes may have the
same id() value. ...
Determining 32 vs 64 bit in C++
... way to reliably determine whether C++ code is being compiled in 32 vs 64 bit. We've come up with what we think is a reasonable solution using macros, but was curious to know if people could think of cases where this might fail or if there is a better way to do this. Please note we are trying to do ...
How do I avoid capturing self in blocks when implementing an API?
I have a working app and I'm working on converting it to ARC in Xcode 4.2. One of the pre-check warnings involves capturing self strongly in a block leading to a retain cycle. I've made a simple code sample to illustrate the issue. I believe I understand what this means but I'm not sure the "corre...
What is the best way to implement nested dictionaries?
...data structure which essentially amounts to a nested dictionary. Let's say it looks like this:
21 Answers
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Are there legitimate uses for JavaScript's “with” statement?
Alan Storm's comments in response to my answer regarding the with statement got me thinking. I've seldom found a reason to use this particular language feature, and had never given much thought to how it might cause trouble. Now, I'm curious as to how I might make effective use of with , while a...
How do I add custom field to Python log format string?
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You could use a LoggerAdapter so you don't have to pass the extra info with every logging call:
import logging
extra = {'app_name':'Super App'}
logger = logging.getLogger(__name__)
syslog = logging.StreamHandler()
formatter = logging.Formatter('%(asctime)s %(app_name)s : %(message)s')
syslog.se...
What's the difference between globals(), locals(), and vars()?
...als() always returns a dictionary of the current namespace
vars() returns either a dictionary of the current namespace (if called with no argument) or the dictionary of the argument.
locals and vars could use some more explanation. If locals() is called inside a function, it updates a dict with t...
How do you calculate the average of a set of circular data? [closed]
...mples from the reading of a compass. The problem of course is how to deal with the wraparound. The same algorithm might be useful for a clockface.
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Django 1.7 - makemigrations not detecting changes
As the title says, I can't seem to get migrations working.
29 Answers
29
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