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Syntax behind sorted(key=lambda: …)
...da function, or if its a particular element in a nested list, tuple, dict, etc., again determined by the lambda function.
Lets try and predict what happens when I run the following code.
mylist = [(3, 5, 8), (6, 2, 8), ( 2, 9, 4), (6, 8, 5)]
sorted(mylist, key=lambda x: x[1])
My sorted call obv...
What is the best way to ensure only one instance of a Bash script is running? [duplicate]
...hat your lock isn't automatically released on kill -9, reboot, power loss, etc.
– Charles Duffy
May 26 '17 at 14:50
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What are fail-safe & fail-fast Iterators in Java
...ific implementations (i.e. the specific collection iterator() / elements() etc methods that return these objects) that specify the behavior. 2) Typical Enumeration implementations are neither fail-fast or fail-safe.
– Stephen C
Feb 5 '16 at 22:56
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How to save MailMessage object to disk as *.eml or *.msg file
... I've found that I also needed to add the <network host="...", etc. in addition to what Ryan provided.
– Steven Rogers
Jul 7 '11 at 20:42
10
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How do I write good/correct package __init__.py files
...-- if "importing the package" means getting all sort of classes, functions etc defined directly as part of the package, then I would lexically copy the contents of blah.py into the package's __init__.py instead and remove blah.py (the multiplication of source files does no good here).
If you do ins...
What blocks Ruby, Python to get Javascript V8 speed? [closed]
...
There are lots of well-known techniques (JIT, modern garbage collector, etc) that could be used to speed up the CPython implementation but all would require substantial changes to the API, breaking most of the extensions in the process. CPython would be faster, but a lot of what makes Python so ...
How to make node.js require absolute? (instead of relative)
...e current directory, then the parent, then grandparent, great-grandparent, etc. is searched. So packages you have installed already work this way. Usually you can require("express") from anywhere in your project and it works fine.
If you find yourself loading common files from the root of your proj...
Do DOM tree elements with ids become global variables?
...e value of the name attribute accessible for form elements (input, select, etc).
Gecko and Webkit incorrectly do NOT make <a> tags accessible via their name attribute.
Gecko incorrectly handles multiple named elements with the same name (it returns a reference to a single node instead of an ar...
Android: upgrading DB version and adding new table
... //alter existing tables(add column, add/remove constraint)
//etc.
}
}
Using Migration classes
onCreate: Since onCreate will be called when application freshly installed, we also need to execute all migrations(database version updates). So onCreate will looks like this:
pu...
Python: Tuples/dictionaries as keys, select, sort
... 'blue'])
for k in blue_fruit:
print k[0], data[k] # prints 'banana 24', etc
Sorting works because tuples have natural ordering if their components have natural ordering.
With keys as rather full-fledged objects, you just filter by k.color == 'blue'.
You can't really use dicts as keys, but yo...