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Why doesn't list have safe “get” method like dictionary?
...tionary and / or returning an item are O(1). It won't be quite as fast in raw terms as checking len, but from a complexity point of view they're all O(1). The right answer is the typical usage / semantics one...
– Mark Longair
Feb 26 '11 at 8:15
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Lists in ConfigParser
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how would this work for raw strings, e.g. key5 : [r"abc $x_i$", r"def $y_j$"] ? They raise the error json.decoder.JSONDecodeError: Expecting value: line 1 column 2 (char 1)
– kingusiu
Apr 9 '19 at 18:09
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jQuery append() - return appended elements
...ngs around by first creating newHtml with jQuery(html [, ownerDocument ]), and then using appendTo(target) (note the "To" bit) to add that it to the end of #mydiv.
Because you now start with $(newHtml) the end result of appendTo('#myDiv') is that new bit of html, and the .effects(...) call will be...
Upgrade Node.js to the latest version on Mac OS
...install nvm and have multiple versions of Node.js installed.
curl https://raw.github.com/creationix/nvm/master/install.sh | sh
source ~/.nvm/nvm.sh
and then run:
nvm install 0.8.22 #(or whatever version of Node.js you want)
you can see what versions you have installed with :
nvm list
and y...
How to use php serialize() and unserialize()
... means to put the structure into a "lower common denominator" that can be handled by things other than PHP, like databases, text files, sockets. The standard PHP function serialize is just a format to express such a thing, it serializes a data structure into a string representation that's unique to ...
gdb: how to print the current line or find the current line number?
list commands prints a set of lines, but I need one single line, where I am and where an error has probably occurred.
5 An...
Show pending migrations in rails
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How do you read the output of this command? If the status of a row is "down", does that mean it's a pending migration?
– Dennis
Feb 13 '15 at 15:00
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Making a mocked method return an argument that was passed to it
... Steve's answer is more generic. This one only allows you to return the raw argument. If you want to process that argument and return the result, then Steve's answer rules. I upvoted both as they are both useful.
– akostadinov
Dec 6 '17 at 13:34
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Get the value of an instance variable given its name
...variable_get("@#{name}")
There is no need to use + or intern; Ruby will handle this just fine. However, if you find yourself reaching into another object and pulling out its ivar, there's a reasonably good chance that you have broken encapsulation.
If you explicitly want to access an ivar, the ri...
Pinging servers in Python
...sing this module, you need root access due to the fact that it is crafting raw packets under the hood.
import pyping
r = pyping.ping('google.com')
if r.ret_code == 0:
print("Success")
else:
print("Failed with {}".format(r.ret_code))
...