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Why do you need explicitly have the “self” argument in a Python method?
... to make things like this explicit rather than based on a rule.
Additionally, since nothing is implied or assumed, parts of the implementation are exposed. self.__class__, self.__dict__ and other "internal" structures are available in an obvious way.
...
Importing from a relative path in Python
...his method is still commonly used in some situations, where you aren't actually ever 'installing' your package. For example, it's popular with Django users.
You can add Common/ to your sys.path (the list of paths python looks at to import things):
import sys, os
sys.path.append(os.path.join(os.p...
Tracking the script execution time in PHP
...";
echo "It spent " . rutime($ru, $rustart, "stime") .
" ms in system calls\n";
Note that you don't need to calculate a difference if you are spawning a php instance for every test.
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What's the difference between echo, print, and print_r in PHP?
...s, although such usage is rare; echo is slightly faster than print. (Personally, I always use echo, never print.)
var_dump prints out a detailed dump of a variable, including its type and the type of any sub-items (if it's an array or an object). print_r prints a variable in a more human-readable f...
Local variables in nested functions
...ints to the local variable cage in the get_petters function.
When you actually call the function, that closure is then used to look at the value of cage in the surrounding scope at the time you call the function. Here lies the problem. By the time you call your functions, the get_petters function i...
Find out how much memory is being used by an object in Python [duplicate]
...and internal structures related to object types and garbage collection. Finally, some python objects have non-obvious behaviors. For instance, lists reserve space for more objects than they have, most of the time; dicts are even more complicated since they can operate in different ways (they have a ...
Best way to iterate through a Perl array
...ay elements occurs. ($_ is aliased to the element in #1, but #2 and #3 actually copy the scalars from the array.)
#5 might be similar.
In terms memory usage: They're all the same except for #5.
for (@a) is special-cased to avoid flattening the array. The loop iterates over the indexes of the array...
Perl flags -pe, -pi, -p, -w, -d, -i, -t?
...eem to be mostly made up of punctuation :-)
The command line switches are all detailed in perlrun. (available from the command line by calling perldoc perlrun)
Going into the options briefly, one-by-one:
-p: Places a printing loop around your command so that it acts on each
line of standard ...
Capturing URL parameters in request.GET
...ll find the request method (in this case "GET", and for submitted forms usually "POST") in request.method. In some cases it's useful to check that it matches what you're expecting.
Update: When deciding whether to use the URL path or the query parameters for passing information, the following may h...
Why does javascript replace only first instance when using replace? [duplicate]
...
You need to set the g flag to replace globally:
date.replace(new RegExp("/", "g"), '')
// or
date.replace(/\//g, '')
Otherwise only the first occurrence will be replaced.
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