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susisu/poly.ts

Last active February 23, 2019 14:36
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poly.ts
const apply = <T, U>(f: (x: T) => U) => (x: T) => f(x);
const foo = <T extends { foo: number }>(x: T) => x.foo;
const foo2 = apply(foo); // : (x: {}) => number;
foo({ foo: 1, bar: 2 }); // OK
foo({}); // error
foo2({ foo: 1, bar: 2 }); // OK
foo2({}); // OK???
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