Closed
Description
TypeScript Version: 2.3
Code
const evenSquares: number[] =
[1, 2, 3, 4]
.map(x => x % 2 === 0 ? x * x : null)
.filter(x => !!x);
with strictNullChecks
enabled.
Expected behavior:
This should type check. The type of evenSquares
should be number[]
.
Actual behavior:
The type of evenSquares
is deduced as (number|null)[]
, despite the null values being removed via the call to .filter
.