Filtering falsy values from arrays
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Posted on The constructor for Boolean values is all you need to filter all falsy values from an array. Keep in mind that this takes out false
, 0
, null
, undefined
, empty strings, and NaN
. If you don’t want that, filter by something more specific.
const values = [
5, null, false, "hi", 0, undefined, { name: "Tim" }, "", true, NaN, [7]
]
// `Boolean` takes out ALL falsy values
values.filter(Boolean)
// ⇒ [5, "hi", { name: "Tim" }, true, [7]]
// `x != null` leaves most falsy values, taking out `null` and `undefined`
values.filter(value => value != null)
// ⇒ [5, false, "hi", 0, { name: "Tim" }, "", true, NaN, [7]]
const values = [
5, null, false, "hi", 0, undefined, { name: "Tim" }, "", true, NaN, [7]
]
// `Boolean` takes out ALL falsy values
values.filter(Boolean)
// ⇒ [5, "hi", { name: "Tim" }, true, [7]]
// `x != null` leaves most falsy values, taking out `null` and `undefined`
values.filter(value => value != null)
// ⇒ [5, false, "hi", 0, { name: "Tim" }, "", true, NaN, [7]]
const values = [
5, null, false, "hi", 0, undefined, { name: "Tim" }, "", true, NaN, [7]
]
// `Boolean` takes out ALL falsy values
values.filter(Boolean)
// ⇒ [5, "hi", { name: "Tim" }, true, [7]]
// `x != null` leaves most falsy values, taking out `null` and `undefined`
values.filter(value => value != null)
// ⇒ [5, false, "hi", 0, { name: "Tim" }, "", true, NaN, [7]]
const values = [
5, null, false, "hi", 0, undefined, { name: "Tim" }, "", true, NaN, [7]
]
// `Boolean` takes out ALL falsy values
values.filter(Boolean)
// ⇒ [5, "hi", { name: "Tim" }, true, [7]]
// `x != null` leaves most falsy values, taking out `null` and `undefined`
values.filter(value => value != null)
// ⇒ [5, false, "hi", 0, { name: "Tim" }, "", true, NaN, [7]]