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Linq code to select one item
...throws. First() and FirstOrDefault() stop on the first match, so they are more efficient.
Of the First() and Single() family, here's where they throw:
First() - throws if empty/not found, does not throw if duplicate
FirstOrDefault() - returns default if empty/not found, does not throw if duplica...
How to check if a string contains a substring in Bash
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Suppressing deprecated warnings in Xcode
...trating for newbs. Try it where? How do I find target settings? A little more explanation would increase the value of this answer.
– noogrub
Oct 14 '12 at 11:36
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What is the difference between the Facade and Adapter Pattern?
...he shades too. That's a Facade - one button/function that takes care of a more complicated set of steps.
The Adapter pattern just links two incompatible interfaces.
EDIT: A quick analogy for the Adapter pattern (based on the comments) might be something like a DVI-to-VGA adapter. Modern video ca...
Best way to handle list.index(might-not-exist) in python?
...d this is hardly that. I wouldn't have such a problem if the exception was more specific than ValueError.
– Draemon
Jan 25 '10 at 14:06
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Implementing Comments and Likes in database
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Assuming a user can like multiple entities, a same tag can be used for more than one entity but a comment is entity-specific, your model could look like this:
BTW, there are roughly 3 ways to implement the "ER category":
All types in one table.
All concrete types in separate tables.
All c...
Why isn't Python very good for functional programming? [closed]
...stion is: why isn't Python very good for functional programming? Are there more reasons than its lack of pattern matching and algebraic data types? Or are these concepts so important to functional programming that a language that doesn't support them can only be classed as a second rate functional p...
How to select rows from a DataFrame based on column values?
...te the parentheses. Due to Python's operator precedence rules, & binds more tightly than <= and >=. Thus, the parentheses in the last example are necessary. Without the parentheses
df['column_name'] >= A & df['column_name'] <= B
is parsed as
df['column_name'] >= (A &...
Difference between “and” and && in Ruby?
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