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Why does typeof NaN return 'number'?
...eration
which return NaN:
Operations with a NaN as at least one operand
Indeterminate forms
The divisions 0/0, ∞/∞, ∞/−∞, −∞/∞, and −∞/−∞
The multiplications 0×∞ and 0×−∞
The power 1^∞
The additions ∞ + (−∞), (−∞) + ∞ and e...
What is a non-capturing group in regular expressions?
How are non-capturing groups, i.e. (?:) , used in regular expressions and what are they good for?
15 Answers
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How can I repeat a character in Bash?
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You can use:
printf '=%.0s' {1..100}
How this works:
Bash expands {1..100} so the command becomes:
printf '=%.0s' 1 2 3 4 ... 100
I've set printf's format to =%.0s which means that it will always print a single = no matter what argument it is given. Therefore it prints 100 =s.
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Using python map and other functional tools
This is quite n00bish, but I'm trying to learn/understand functional programming in python. The following code:
9 Answers
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What is the JSF resource library for and how should it be used?
The JSF <h:outputStylesheet> , <h:outputScript> and <h:graphicImage> components have a library attribute. What is this and how should this be used? There are a lot of examples on the web which use it as follows with the common content/file type css , js and img (or ima...
What is Weak Head Normal Form?
...es Weak Head Normal Form (WHNF) mean? What does Head Normal form (HNF) and Normal Form (NF) mean?
6 Answers
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Is there a valid reason for enforcing a maximum width of 80 characters in a code file, this day and
... column rule:
To avoid wrapping when copying code into email, web pages, and books.
To view multiple source windows side-by-side or using a side-by-side diff viewer.
To improve readability. Narrow code can be read quickly without having to scan your eyes from side to side.
I think the last point...
jQuery deferreds and promises - .then() vs .done()
I've been reading about jQuery deferreds and promises and I can't see the difference between using .then() & .done() for successful callbacks. I know Eric Hynds mentions that .done() and .success() map to the same functionality but I'm guessing so does .then() as all the callbacks are al...
DateTime2 vs DateTime in SQL Server
...datetime2. Here is their recommendation:
Use the time, date, datetime2 and
datetimeoffset data types for new
work. These types align with the SQL
Standard. They are more portable.
time, datetime2 and datetimeoffset
provide more seconds precision.
datetimeoffset provides time zone
s...
Should I use #define, enum or const?
.... Those four flags can be combined. Flags describe the records in database and can be:
15 Answers
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