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How to override the [] operator in Python?
...thod.
class MyClass:
def __getitem__(self, key):
return key * 2
myobj = MyClass()
myobj[3] #Output: 6
And if you're going to be setting values you'll need to implement the __setitem__ method too, otherwise this will happen:
>>> myobj[5] = 1
Traceback (most recent call last)...
What is causing ERROR: there is no unique constraint matching given keys for referenced table?
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203
It's because the name column on the bar table does not have the UNIQUE constraint.
So imagine...
How can I tell Rails to use RSpec instead of test-unit when creating a new Rails app?
...talled (along with -core , -expectations , -mocks and -rails version 2.6.x). When I run the command rails new foo , it uses test-unit to generate the test stub files instead of rspec .
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Git: show more context when using git add -i or git add -e?
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Convert to absolute value in Objective-C
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How do you run a single query through mysql from the command line?
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250
mysql -u <user> -p -e "select * from schema.table"
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Node.js + Express: Routes vs controller
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SQLite table constraint - unique on multiple columns
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Martin Tournoij
22.1k1717 gold badges8585 silver badges116116 bronze badges
answered Apr 23 '10 at 20:50
Ayman Hourie...