# reduce abstract method

T reduce(

1. T identity,
2. T accumulator(
   1. T,
   2. T
   )

)

Performs a reduction on the elements of this stream, using the provided identity value and an associative accumulation function, and returns the reduced value.

## Example

    final sum = GenericStream.of([1, 2, 3, 4, 5])
        .reduce(0, (a, b) => a + b);

## Implementation

    T reduce(T identity, T Function(T, T) accumulator);