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a ? (x) : b => (c) : d => e
which either means
a ? ((x): b => c) : (d => e)
or
a ? x : (b => ((c): d => e))
interface Foo<T> { fn <U extends Partial<T>>(m:U): T extends U ? 1 : 0; } //quad quad quad n < U extends Partial<T>>(m:U): T extends U ? 1: 0_{i} declare const f: Foo<{ m: boolean }>; let k = f.fn({m: false });