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import { inc } from './inc'import { isNil } from './isNil'import { unless } from './unless'
const safeInc = unless(isNil, inc)
test('happy', () => {  expect(safeInc(null)).toBeNull()  expect(safeInc(1)).toBe(2)})
test('curried', () => {  const safeIncCurried = unless(isNil)(inc)  expect(safeIncCurried(null)).toBeNull()  expect(safeIncCurried(1)).toBe(2)})