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by jabagawee 4391 days ago
Oh! So `go` is a function that's defined within `shift`. That's the crucial part I was missing. Why is it named "go"?

EDIT: While I have your attention, do you mind also pointing me to some resources to learn about this ">>=" operator? I recall it's something related to monads...
3 comments
taylorfausak 4391 days ago
As ibotty said, I named the anonymous inner worker function `go`. From what I can tell, it seems to be pretty common in Haskell.

As for `>>=` (also known as `bind`), I'm using it as a more generic version of `concatMap`. The following expressions are basically the same:

    concat (map (\ x -> [x, -x]) [1, 2, 3])
    concatMap (\ x -> [x, -x]) [1, 2, 3]
    [1, 2, 3] >>= \ x -> [x, -x]
If you want to learn more, check out LYAH [1].

[1]: http://learnyouahaskell.com/a-fistful-of-monads

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ibotty 4391 days ago
`go` is a very old name for worker functions in haskell. i have been told it originates in glasgow (where ghc was first developed).
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gu 4391 days ago
The bind operator (>>=) is commonly expressed in 'do' notation. The following two code snippets are equivalent:

do x <- foo; y <- bar; baz x y

foo >>= \x -> bar >>= \y -> baz x y

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