yaa110 / goterator

Lazy iterator implementation for Golang

Goterator

Iterator implementation for Golang to provide map and reduce functionalities.

Package

import (
    "github.com/yaa110/goterator"
    "github.com/yaa110/goterator/generator"
)

Getting Started

• Create a generator from slices

words := []interface{}{"an", "example", "of", "goterator"}

gen := generator.NewSlice(words)

• Create a generator from channels

chn := make(chan interface{}, 4)
chn <- "an"
chn <- "example"
chn <- "of"
chn <- "goterator"
close(chn)

gen := generator.NewChannel(chn)

• Create custom generators

type TestGenerator struct {
    words []string
    i     int
    value string
}

func (g *TestGenerator) Next() bool {
    if g.i == len(g.words) {
        return false
    }
    g.value = g.words[g.i]
    g.i++
    return true
}

func (g *TestGenerator) Value() interface{} {
    return g.value
}

gen := &TestGenerator{
    words: []string{"an", "example", "of", "goterator"},
    i: 0,
    value: "",
}

• Iterate over generators

lengths := goterator.New(gen).Map(func(word interface{}) interface{} {
    return len(word.(string))
}).Collect()

assert.Equal([]interface{}{2, 7, 2, 9}, lengths)

Please for more information about mappers and reducers (consumers) check the documentation.