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Function: reduce()

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.

Example​

console.log(
  pipe(
    [`Hello`, `Sloth!`, `What`, `an`, `interesting`, `program!`],
    reduce((a, b) => `${a} ${b}`),
    get,
  ),
)
//=> Hello Sloth! What an interesting program!

console.log(
  pipe(
    [`Hello`, `Sloth!`, `What`, `an`, `interesting`, `program!`],
    reduce({ create: () => ``, add: (a, b) => `${a} ${b}` }),
  ),
)
//=> Hello Sloth! What an interesting program!

Since​

v0.0.1

Call Signature​

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

Type Parameters​

• Value

• Acc

• Finished

• This

Parameters​

reducer​

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

iterable​

Iterable<Value, any, any>

Returns​

Finished

Defined in​

reducers.d.ts:651

Call Signature​

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

Type Parameters​

• Value

• Acc

• Finished

• This

Parameters​

reducer​

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

Returns​

Function

Parameters​

iterable​

Iterable<Value, any, any>

Returns​

Finished

Defined in​

reducers.d.ts:655

Call Signature​

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

Type Parameters​

• Value

• Acc

• This

Parameters​

reducer​

Readonly<RawReducerWithoutFinish<Value, Acc, This>>

iterable​

Iterable<Value, any, any>

Returns​

Acc

Defined in​

reducers.d.ts:659

Call Signature​

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

Type Parameters​

• Value

• Acc

• This

Parameters​

reducer​

Readonly<RawReducerWithoutFinish<Value, Acc, This>>

Returns​

Function

Parameters​

iterable​

Iterable<Value, any, any>

Returns​

Acc

Defined in​

reducers.d.ts:663

Call Signature​

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

Type Parameters​

• Value

• Finished

• This

Parameters​

reducer​

Readonly<RawOptionalReducerWithFinish<Value, Finished, This>>

iterable​

Iterable<Value, any, any>

Returns​

Optional<Finished>

Defined in​

reducers.d.ts:667

Call Signature​

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

Type Parameters​

• Value

• Finished

• This

Parameters​

reducer​

Readonly<RawOptionalReducerWithFinish<Value, Finished, This>>

Returns​

Function

Parameters​

iterable​

Iterable<Value, any, any>

Returns​

Optional<Finished>

Defined in​

reducers.d.ts:671

Call Signature​

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

Type Parameters​

• Value

• This

Parameters​

reducer​

Readonly<RawOptionalReducerWithoutFinish<Value, This>>

iterable​

Iterable<Value, any, any>

Returns​

Optional<Value>

Defined in​

reducers.d.ts:675

Call Signature​

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

Type Parameters​

• Value

• This

Parameters​

reducer​

Readonly<RawOptionalReducerWithoutFinish<Value, This>>

Returns​

Function

Parameters​

iterable​

Iterable<Value, any, any>

Returns​

Optional<Value>

Defined in​

reducers.d.ts:679

Call Signature​

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

Type Parameters​

• Value

Parameters​

reducer​

FunctionReducer<Value>

iterable​

Iterable<Value, any, any>

Returns​

Optional<Value>

Defined in​

reducers.d.ts:683

Call Signature​

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

Type Parameters​

• Value

Parameters​

reducer​

FunctionReducer<Value>

Returns​

Function

Parameters​

iterable​

Iterable<Value, any, any>

Returns​

Optional<Value>

Defined in​

reducers.d.ts:687