gostream

README

gostream

Installation

$ go install github.com/nmi/gostream

Usage

See stream_test.go for other functions.

// repeat: 1, 2, 3, 1, 2, 3
repeat := gostream.GenerateRepeatStream(ctx, 1, 2, 3)

// samenum: 1000, 1000, 1000, ...
samenum := gostream.GenerateRepeatStream(ctx, 1000)

// random: 3, 3843029809, 11, ... (for example)
random := gostream.GenerateRandIntsStream(ctx)

Benchmark

For some workloads, multiple streams run in parallel and scale with the number of CPUs.

$ for i in `seq 1 4`; do go test -bench=. -cpu=$i | grep "ns/op"; done
BenchmarkAppendStringsStream             1000000              1108 ns/op  # 1 CPU
BenchmarkAppendStringsStream-2           1000000              1439 ns/op  # 2 CPU
BenchmarkAppendStringsStream-3           1000000              1774 ns/op  # 3 CPU
BenchmarkAppendStringsStream-4           1000000              1992 ns/op  # 4 CPU

Documentation

Overview

Package gostream provides utility functions for channel processing

Index

• func GenerateRandIntsStream(ctx context.Context) <-chan interface{}
• func GenerateRepeatStream(ctx context.Context, list ...interface{}) <-chan interface{}
• func GenerateSerialIntsStream(ctx context.Context) <-chan interface{}
• func Map(ctx context.Context, f func(args ...interface{}) interface{}, ...) <-chan interface{}
• func Merge(ctx context.Context, inStreams ...<-chan interface{}) <-chan interface{}
• func Take(ctx context.Context, inStream <-chan interface{}, num int) <-chan interface{}

Functions

func GenerateRandIntsStream

func GenerateRandIntsStream(ctx context.Context) <-chan interface{}

GenerateRandIntsStream generates a random integer sequence infinitely.

func GenerateRepeatStream

func GenerateRepeatStream(ctx context.Context, list ...interface{}) <-chan interface{}

GenerateRepeatStream generates all elemtnes of the list infinitely

func GenerateSerialIntsStream

func GenerateSerialIntsStream(ctx context.Context) <-chan interface{}

GenerateSerialIntsStream produces an infinite serial integer sequence in ascending order.

func Map

func Map(ctx context.Context,
	f func(args ...interface{}) interface{},
	inStreams ...<-chan interface{}) <-chan interface{}

Map first applies the function f to the first element of all input streams. Also, Map does the same for the second and subsequent elements.

func Merge

func Merge(ctx context.Context, inStreams ...<-chan interface{}) <-chan interface{}

Merge combines multiple streams into one stream.

func Take

func Take(ctx context.Context, inStream <-chan interface{}, num int) <-chan interface{}

Take takes the top num items from the input stream.