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Variable: reduce()

const reduce: {<Value, Acc, Finished, This>(reducer, iterable): Finished; <Value, Acc, Finished, This>(reducer): (iterable) => Finished; <Value, Acc, This>(reducer, iterable): Acc; <Value, Acc, This>(reducer): (iterable) => Acc; <Value, Finished, This>(reducer, iterable): Optional<Finished>; <Value, Finished, This>(reducer): (iterable) => Optional<Finished>; <Value, This>(reducer, iterable): Optional<Value>; <Value, This>(reducer): (iterable) => Optional<Value>; <Value>(reducer, iterable): Optional<Value>; <Value>(reducer): (iterable) => Optional<Value>; }

Defined in: reducers.d.ts:642

Returns the result of reducing iterable using reducer.

An initial accumulator is created using RawReducerWithoutFinish.create. Then each value in iterable is added to the accumulator and the current accumulator is updated using RawReducerWithoutFinish.add. Finally, the resulting accumulator is transformed using RawReducerWithFinish.finish if specified.

If reducer is an optional reducer (no RawReducerWithoutFinish.create method), then an empty iterable is returned if iterable is empty. Otherwise, an iterable containing the result of reducing using the first value of the iterable as the initial accumulator is returned.

Like Array.prototype.reduce, but for iterables.

Call Signature​

<Value, Acc, Finished, This>(reducer, iterable): Finished

Type Parameters​

Value​

Value

Acc​

Acc

Finished​

Finished

This​

This

Parameters​

reducer​

Readonly<RawReducerWithFinish<Value, Acc, Finished, This>>

iterable​

Iterable<Value>

Returns​

Finished

Call Signature​

<Value, Acc, Finished, This>(reducer): (iterable) => Finished

Type Parameters​

Value​

Value

Acc​

Acc

Finished​

Finished

This​

This

Parameters​

reducer​

Readonly<RawReducerWithFinish<Value, Acc, Finished, This>>

Returns​

(iterable): Finished

Parameters​

iterable​

Iterable<Value>

Returns​

Finished

Call Signature​

<Value, Acc, This>(reducer, iterable): Acc

Type Parameters​

Value​

Value

Acc​

Acc

This​

This

Parameters​

reducer​

Readonly<RawReducerWithoutFinish<Value, Acc, This>>

iterable​

Iterable<Value>

Returns​

Acc

Call Signature​

<Value, Acc, This>(reducer): (iterable) => Acc

Type Parameters​

Value​

Value

Acc​

Acc

This​

This

Parameters​

reducer​

Readonly<RawReducerWithoutFinish<Value, Acc, This>>

Returns​

(iterable): Acc

Parameters​

iterable​

Iterable<Value>

Returns​

Acc

Call Signature​

<Value, Finished, This>(reducer, iterable): Optional<Finished>

Type Parameters​

Value​

Value

Finished​

Finished

This​

This

Parameters​

reducer​

Readonly<RawOptionalReducerWithFinish<Value, Finished, This>>

iterable​

Iterable<Value>

Returns​

Optional<Finished>

Call Signature​

<Value, Finished, This>(reducer): (iterable) => Optional<Finished>

Type Parameters​

Value​

Value

Finished​

Finished

This​

This

Parameters​

reducer​

Readonly<RawOptionalReducerWithFinish<Value, Finished, This>>

Returns​

(iterable): Optional<Finished>

Parameters​

iterable​

Iterable<Value>

Returns​

Optional<Finished>

Call Signature​

<Value, This>(reducer, iterable): Optional<Value>

Type Parameters​

Value​

Value

This​

This

Parameters​

reducer​

Readonly<RawOptionalReducerWithoutFinish<Value, This>>

iterable​

Iterable<Value>

Returns​

Optional<Value>

Call Signature​

<Value, This>(reducer): (iterable) => Optional<Value>

Type Parameters​

Value​

Value

This​

This

Parameters​

reducer​

Readonly<RawOptionalReducerWithoutFinish<Value, This>>

Returns​

(iterable): Optional<Value>

Parameters​

iterable​

Iterable<Value>

Returns​

Optional<Value>

Call Signature​

<Value>(reducer, iterable): Optional<Value>

Type Parameters​

Value​

Value

Parameters​

reducer​

FunctionReducer<Value>

iterable​

Iterable<Value>

Returns​

Optional<Value>

Call Signature​

<Value>(reducer): (iterable) => Optional<Value>

Type Parameters​

Value​

Value

Parameters​

reducer​

FunctionReducer<Value>

Returns​

(iterable): Optional<Value>

Parameters​

iterable​

Iterable<Value>

Returns​

Optional<Value>

Example​

console.log(
  pipe(
    [`sloth`, `more sloth`, `even more sloth`],
    map(string => string.length),
    reduce(toArray()),
  ),
)
//=> [ 5, 10, 15 ]
Playground

Since​

v0.0.1