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namedtuple and default values for optional keyword arguments
...lds)
>>> Node()
Node(val=None, left=None, right=None)
Order
In all versions of Python, if you set fewer default values than exist in the namedtuple, the defaults are applied to the rightmost parameters. This allows you to keep some arguments as required arguments.
>>> Node.__ne...
Do I need to explicitly call the base virtual destructor?
...the destructor again as virtual on the inheriting class, but do I need to call the base destructor?
7 Answers
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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...
Does Python have a string 'contains' substring method?
...methods to make in available to your custom type.
– BallpointBen
Aug 17 '18 at 7:02
31
Just make ...
PHP equivalent of .NET/Java's toString()
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@MarkAmery He gave an answer that implicitly calls the __toString() "Magic Method", but didn't mention that at all. The user asked for an answer that was like the Java toString() method, and in PHP, that's the __toString() function.
– Supuhstar
...
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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multiprocessing.Pool: When to use apply, apply_async or map?
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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...
C Macro definition to determine big endian or little endian machine?
...
Code supporting arbitrary byte orders, ready to be put into a file called order32.h:
#ifndef ORDER32_H
#define ORDER32_H
#include <limits.h>
#include <stdint.h>
#if CHAR_BIT != 8
#error "unsupported char size"
#endif
enum
{
O32_LITTLE_ENDIAN = 0x03020100ul,
O32_BIG_END...
GET URL parameter in PHP
...perglobal: a built-in variable that's populated by PHP and is available in all scopes (you can use it from inside a function without the global keyword).
Since the variable might not exist, you could (and should) ensure your code does not trigger notices with:
<?php
if (isset($_GET['link'])) {
...
Why are all fields in an interface implicitly static and final?
I am just trying to understand why all fields defined in an Interface are implicitly static and final . The idea of keeping fields static makes sense to me as you can't have objects of an interface but why they are final (implicitly)?
...