List comprehensions: Difference between revisions
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List comprehension notation was not, in the end, included in the final ES6 standard, and the code above will not run in fully ES6-compliant browsers or interpreters, but we can still go straight to the underlying monadic logic of list comprehensions and obtain:
<code>[(x,y,z) | x <- [1..n], y <- [x..n], z <- [y..n], x^2 + y^2 == z^2]</code>
by using concatMap (the monadic bind function for lists), and x => [x] (monadic return for lists):
<lang JavaScript>(
'use strict';
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length: Math.floor(n - m) + 1
}, (_, i) => m + i);
// EXAMPLE ----------------------------------------------------------------
// xs :: [Int]
const xs = enumFromTo(1,
return concatMap(x =>
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] : [],
enumFromTo(1, n));
})(20);</lang>
{{Out}}
<lang JavaScript>[[3, 4, 5], [5, 12, 13], [6, 8, 10], [8, 15, 17], [9, 12, 15], [12, 16, 20]]</lang>
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