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My attempt at value initialization is interpreted as a function declaration, and why doesn't A a(())
...n of the language.
If you do have an expression within then it is valid. For example:
((0));//compiles
Even simpler put: because (x) is a valid C++ expression, while () is not.
To learn more about how languages are defined, and how compilers work, you should learn about Formal language theor...
What are some uses of template template parameters?
...on to deal with all specializations of H.
NOTE: I've been programming c++ for many years and have only needed this once. I find that it is a rarely needed feature (of course handy when you need it!).
I've been trying to think of good examples, and to be honest, most of the time this isn't necessar...
Why do you have to call .items() when iterating over a dictionary in Python?
...
For every python container C, the expectation is that
for item in C:
assert item in C
will pass just fine -- wouldn't you find it astonishing if one sense of in (the loop clause) had a completely different meaning from...
Will using 'var' affect performance?
...les use the varkeyword and got the answer that while it is only necessary for anonymous types, that it is used nonetheless to make writing code 'quicker'/easier and 'just because'.
...
Selecting multiple columns in a pandas dataframe
...can sometimes alter the original object. Always good to be on the look out for this.
df1 = df.iloc[0, 0:2].copy() # To avoid the case where changing df1 also changes df
To use iloc, you need to know the column positions (or indices). As the column positions may change, instead of hard-coding indice...
MongoDB atomic “findOrCreate”: findOne, insert if nonexistent, but do not update
as the title says, I want to perform a find (one) for a document, by _id, and if doesn't exist, have it created, then whether it was found or was created, have it returned in the callback.
...
Fitting empirical distribution to theoretical ones with Scipy (Python)?
... values in the list are not necessarily in order, but order doesn't matter for this problem.
9 Answers
...
_DEBUG vs NDEBUG
...lf that defines these macros and not Visual Studio (the IDE). Thanks a lot for this answer!
– Niklas R
Jul 24 '15 at 11:26
...
“Incorrect string value” when trying to insert UTF-8 into MySQL via JDBC?
... file. It seems that Connector/J defaults to 3-byte Unicode otherwise:
For example, to use 4-byte UTF-8 character sets with Connector/J, configure the MySQL server with character_set_server=utf8mb4, and leave characterEncoding out of the Connector/J connection string. Connector/J will then autod...
How to make a python, command-line program autocomplete arbitrary things NOT interpreter
...
Use Python's readline bindings. For example,
import readline
def completer(text, state):
options = [i for i in commands if i.startswith(text)]
if state < len(options):
return options[state]
else:
return None
readline.parse_...