<A, K extends string | symbol>(
items: Iterable<A>,
f: (a: A) => K
): Record<ReadonlyRecord.NonLiteralKey<K>, A>Creates a new record from an iterable, utilizing the provided function to determine the key for each element.
Example (Building a record keyed by iterable values)
import { Record } from "effect"
import * as assert from "node:assert"
const users = [
{ id: "2", name: "name2" },
{ id: "1", name: "name1" }
]
assert.deepStrictEqual(
Record.fromIterableBy(users, (user) => user.id),
{
"2": { id: "2", name: "name2" },
"1": { id: "1", name: "name1" }
}
)constructors
Source effect/Record.ts:2834 lines
export const const fromIterableBy: <
A,
K extends string | symbol
>(
items: Iterable<A>,
f: (a: A) => K
) => Record<ReadonlyRecord.NonLiteralKey<K>, A>
Creates a new record from an iterable, utilizing the provided function to determine the key for each element.
Example (Building a record keyed by iterable values)
import { Record } from "effect"
import * as assert from "node:assert"
const users = [
{ id: "2", name: "name2" },
{ id: "1", name: "name1" }
]
assert.deepStrictEqual(
Record.fromIterableBy(users, (user) => user.id),
{
"2": { id: "2", name: "name2" },
"1": { id: "1", name: "name1" }
}
)
fromIterableBy = <function (type parameter) A in <A, K extends string | symbol>(items: Iterable<A>, f: (a: A) => K): Record<ReadonlyRecord.NonLiteralKey<K>, A>A, function (type parameter) K in <A, K extends string | symbol>(items: Iterable<A>, f: (a: A) => K): Record<ReadonlyRecord.NonLiteralKey<K>, A>K extends string | symbol>(
items: Iterable<A>items: interface Iterable<T, TReturn = any, TNext = any>Iterable<function (type parameter) A in <A, K extends string | symbol>(items: Iterable<A>, f: (a: A) => K): Record<ReadonlyRecord.NonLiteralKey<K>, A>A>,
f: (a: A) => Kf: (a: Aa: function (type parameter) A in <A, K extends string | symbol>(items: Iterable<A>, f: (a: A) => K): Record<ReadonlyRecord.NonLiteralKey<K>, A>A) => function (type parameter) K in <A, K extends string | symbol>(items: Iterable<A>, f: (a: A) => K): Record<ReadonlyRecord.NonLiteralKey<K>, A>K
): type Record<K extends keyof any, T> = {
[P in K]: T
}
Construct a type with a set of properties K of type T
Record<ReadonlyRecord.type ReadonlyRecord<in out K extends string | symbol, out A>.NonLiteralKey<K extends string | symbol> = K extends string ? ReadonlyRecord.IsFiniteString<K> extends true ? string : K : symbolRepresents a type that converts literal string keys to generic string type and symbol keys to generic symbol type.
This is useful for maintaining type safety while allowing flexible key types in record operations.
Example (Converting literal keys to non-literal keys)
import type { Record } from "effect"
// For literal string keys, this becomes 'string'
type Example1 = Record.ReadonlyRecord.NonLiteralKey<"foo" | "bar"> // string
// For symbol keys, this becomes 'symbol'
type Example2 = Record.ReadonlyRecord.NonLiteralKey<symbol> // symbol
NonLiteralKey<function (type parameter) K in <A, K extends string | symbol>(items: Iterable<A>, f: (a: A) => K): Record<ReadonlyRecord.NonLiteralKey<K>, A>K>, function (type parameter) A in <A, K extends string | symbol>(items: Iterable<A>, f: (a: A) => K): Record<ReadonlyRecord.NonLiteralKey<K>, A>A> => const fromIterableWith: <A, K, A>(self: Iterable<A>, f: (a: A) => readonly [K, A]) => Record<ReadonlyRecord<in out K extends string | symbol, out A>.NonLiteralKey<K>, A> (+1 overload)fromIterableWith(items: Iterable<A>items, (a: Aa) => [f: (a: A) => Kf(a: Aa), a: Aa])