From 87bc14857077846ffc39e2878a475020eb7a15d2 Mon Sep 17 00:00:00 2001
From: milarin <milaring@proton.me>
Date: Tue, 14 May 2024 20:26:58 +0200
Subject: [PATCH] more filter functions

---
 filter.go | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/filter.go b/filter.go
index 873f7c1..d99059d 100644
--- a/filter.go
+++ b/filter.go
@@ -1,6 +1,6 @@
 package channel
 
-func Filter[T any](source <-chan T, filter func(T) bool) <-chan T {
+func FilterSuccessive[T any](source <-chan T, filter func(T) bool) <-chan T {
 	out := make(chan T, cap(source))
 
 	go func() {
@@ -14,3 +14,26 @@ func Filter[T any](source <-chan T, filter func(T) bool) <-chan T {
 
 	return out
 }
+
+func Filter[T any](source <-chan T, filter func(T) bool) <-chan T {
+	return FilterPreserveOrderWithRunner(source, getDefaultRunner(), filter)
+}
+
+func FilterPreserveOrderWithRunner[T any](source <-chan T, runner Runner, filter func(T) bool) <-chan T {
+	type FilteredValue[T any] struct {
+		Value  T
+		Filter bool
+	}
+
+	mappedValues := MapPreserveOrderWithRunner(source, runner, func(value T) FilteredValue[T] {
+		return FilteredValue[T]{Value: value, Filter: filter(value)}
+	})
+
+	filteredValues := FilterSuccessive(mappedValues, func(filteredValue FilteredValue[T]) bool {
+		return filteredValue.Filter
+	})
+
+	return MapSuccessive(filteredValues, func(filteredValue FilteredValue[T]) T {
+		return filteredValue.Value
+	})
+}