`&:views_count` in `Post.published.collect(&:views_count)` [duplicate]

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This is actually a rather clever hack made it into ruby 1.9.

Basically, & in front of a variable in ruby coerces it into a proc. It does that by calling to_proc. Some clever fellow (first time I saw this was in _whys code, but I won’t credit him cause I don’t know if he came up with it) added a to_proc method to Symbol, that is essentially {|obj| obj.send self}.

There aren’t many coercians in ruby, but it seems like all of them are mostly used to do hacks like this (like !! to coerce any type into a boolean)

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