This seems to be a recurring pattern that results in lots of copy/paste code
go get github.com/Sinea/fork- Slice
- Chan
- Map keys
- Map values
- Iterator
- Channel
- Slice
Fork from slice with concurrency of 3 and join results into a channel
input := []string{"dog", "cat", "moose"}
lengths := fork.
Slice[string, int](input).
Concurrency(3).
JoinChan(func(value string) (int, bool) {
return len(value), false
})Fork from a channel and get the result as a slice
input := make(chan int)
squares := fork.
Chan[int, int](input).
Concurrency(3).
JoinSlice(func(value int) (int, bool) {
return value*value, false
})Signal an early exit
input := []int{1, 2, 3}
squares := fork.
Slice[int, int](input).
Concurrency(3).
JoinChan(func(value int) (int, bool) {
// This signals that we want to stop. Maybe be triggered by an error... who knows
return value*value, true
})Fork from map values to a channel
input := map[string]int{
"zero": 0,
"one": 1,
"two": 2,
}
valueSquares := fork.
Values[string, int, int](input).
JoinChan(func(value int) (int, bool) {
return value*value, false
})Fork from map keys to a channel
input := map[int]string{
0: "zero",
1: "one",
2: "two",
}
keySquares := fork.
Keys[int, string, int](input).
JoinSlice(func(value int) (int, bool) {
return value*value, false
})Fork from a custom iterator
type tickerIterator struct {
ticker *time.Ticker
deadline time.Time
}
func (c *tickerIterator) Open() {
}
func (c *tickerIterator) Close() {
c.ticker.Stop()
}
func (c *tickerIterator) Next() (*time.Time, bool) {
t, ok := <-c.ticker.C
if time.Now().After(c.deadline) {
return nil, false
}
return &t, ok
}
source := &tickerIterator{
ticker: time.NewTicker(time.Second),
deadline: time.Now().Add(time.Second * 5),
}
output := fork.Iter[*time.Time, int64](source).
JoinSlice(func(input *time.Time) (output int64, terminate bool) {
return input.UnixMilli(), false
})
// output should contain the unix millis from the ticker generated time.Time
fmt.Println(output)