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hasNext in Python iterators?
...thod to put the first element back after I have checked that it exists by calling next().
– Giorgio
Dec 24 '12 at 20:26
16
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PHP - include a php file and also send query parameters
...luded PHP file which will then be interpreted. There is no scope change at all, so you can still access $someVar in the included file directly (even though you might consider a class based structure where you pass $someVar as a parameter or refer to a few global variables).
...
How do I avoid capturing self in blocks when implementing an API?
...ied inside the block (we're not doing that) but also they are not automatically retained when the block is retained (unless you are using ARC). If you do this, you must be sure that nothing else is going to try to execute the block after the MyDataProcessor instance is released. (Given the structure...
Pandas - How to flatten a hierarchical index in columns
..., but leaves behind column names which are difficult to access programmatically and are not queriable
– dmeu
Jun 29 '17 at 8:53
1
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How can I check if a string represents an int, without using try/except?
...
If you're really just annoyed at using try/excepts all over the place, please just write a helper function:
def RepresentsInt(s):
try:
int(s)
return True
except ValueError:
return False
>>> pri...
How to join components of a path when you are constructing a URL in Python
...
Specifically once I have that the prefix has to ends in / and that the target path can't begin in / I might as well just concatenate. In this case I am not sure if urljoin is really helping?
– amjoconn
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Importing a CSV file into a sqlite3 database table using Python
...lumn headers in the csv file. And close the connection to the database by calling con.close() at the end.
– Jonas
Aug 8 '16 at 21:31
1
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Does reading an entire file leave the file handle open?
...hat on the particular Python implementation.
To understand what this is all about, pay particular attention to the actual file object. In your code, that object is mentioned only once, in an expression, and becomes inaccessible immediately after the read() call returns.
This means that the file...
multiprocessing.Pool: When to use apply, apply_async or map?
...
Back in the old days of Python, to call a function with arbitrary arguments, you would use apply:
apply(f,args,kwargs)
apply still exists in Python2.7 though not in Python3, and is generally not used anymore. Nowadays,
f(*args,**kwargs)
is preferred. The...
Reference — What does this symbol mean in PHP?
... have the same results.
Pre-increment is a little bit faster because it really increments the variable and after that 'returns' the result. Post-increment creates a special variable, copies there the value of the first variable and only after the first variable is used, replaces its value with seco...