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Python != operation vs “is not”
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@viksit. None has few methods and almost no attributes. If your __eq__ test expected a method or attribute, it might break. def __eq__( self, other ): return self.size == other.size. For example, will break if other happens to be None.
– S.Lott
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Incrementing in C++ - When to use x++ or ++x?
...and please note that in a for loop, on primatives, there is absolutely no difference. Many coding styles will recommend never using an increment operator where it could be misunderstood; i.e., x++ or ++x should only exist on its own line, never as y=x++. Personally, I don't like this, but it's unco...
What is the size of column of int(11) in mysql in bytes?
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An INT will always be 4 bytes no matter what length is specified.
TINYINT = 1 byte (8 bit)
SMALLINT = 2 bytes (16 bit)
MEDIUMINT = 3 bytes (24 bit)
INT = 4 bytes (32 bit)
BIGINT = 8 bytes (64 bit).
The length just specifies how many characters to pad when selecting data with the ...
How to conditionally push an item in an observable array?
I would like to push a new item onto an observableArray , but only if the item is not already present. Is there any "find" function or recommended pattern for achieving this in KnockoutJS?
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Django migration strategy for renaming a model and relationship fields
...nameField('YetAnotherModel', 'foo', 'bar')
]
You may get some errors if you don't update the names where it's imported e.g. admin.py and even older migration files (!).
Update: As ceasaro mentions, newer versions of Django are usually able to detect and ask if a model is renamed. So try manag...
How do I update my bare repo?
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If you want to duplicate all the objects from the main repo, do this inside the main repo:
git push --all <url-of-bare-repo>
Alternatively, do a fetch inside the bare repo:
git fetch <url-of-main-repo>
You c...
Count the number occurrences of a character in a string
...nswers said, using the string method count() is probably the simplest, but if you're doing this frequently, check out collections.Counter:
from collections import Counter
my_str = "Mary had a little lamb"
counter = Counter(my_str)
print counter['a']
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How to set username and password for SmtpClient object in .NET?
I see different versions of the constructor, one uses info from web.config, one specifies the host, and one the host and port. But how do I set the username and password to something different from the web.config? We have the issue where our internal smtp is blocked by some high security clients and...
In Objective-C, what is the equivalent of Java's “instanceof” keyword?
...bject ) is assignable (cast-able) to a variable of another type (e.g. SpecifiedType ). In Java, I can write:
3 Answers
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Is it safe to get values from a java.util.HashMap from multiple threads (no modification)?
...a map will be constructed, and once it is initialized, it will never be modified again. It will however, be accessed (via get(key) only) from multiple threads. Is it safe to use a java.util.HashMap in this way?
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