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@extra-array/count-as

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function id(v) { return v; } function countAs(x, fm = null) { var fm = fm || id; var a = new Map(), i = -1; for (var v of x) { var v1 = fm(v, ++i, x); a.set(v1, (a.get(v1) || 0) + 1); } return a; } export { countAs as default };