✨ [collection] Added execute a function on each element of a function

Author: acabarbaye

changes/20251117162958.feature

@@ -0,0 +1 @@
+:sparkles: `[collection]` Added execute a function on each element of a function

changes/20251117163045.feature

@@ -0,0 +1 @@
+:zap: `[collection]` Support `iter.Seq` for most operations on slices (map, filter) to increase performance

changes/20251117163100.feature

@@ -0,0 +1 @@
+:sparkles: `[collection]` Added set operations on slices

utils/collection/conditions.go

@@ -1,6 +1,9 @@
 package collection
 
 import (
+	"iter"
+	"slices"
+
 	"github.com/ARM-software/golang-utils/utils/commonerrors"
 )
 
@@ -120,11 +123,16 @@ func (c *Conditions) OneHot() bool {
 
 // Any returns true if there is at least one element of the slice which is true.
 func Any(slice []bool) bool {
-	if len(slice) == 0 {
+	return AnySequence(slices.Values(slice))
+}
+
+// AnySequence returns true if there is at least one element of the slice which is true.
+func AnySequence(seq iter.Seq[bool]) bool {
+	if seq == nil {
 		return false
 	}
-	for i := range slice {
-		if slice[i] {
+	for e := range seq {
+		if e {
 			return true
 		}
 	}
@@ -136,17 +144,31 @@ func AnyTrue(values ...bool) bool {
 	return Any(values)
 }
 
-// All returns true if all items of the slice are true.
-func All(slice []bool) bool {
-	if len(slice) == 0 {
-		return false
-	}
-	for i := range slice {
-		if !slice[i] {
-			return false
+// AnyFalseSequence returns true if there is at least one element of the sequence which is false.
+func AnyFalseSequence(eq iter.Seq[bool]) bool {
+	hasElements := false
+	for e := range eq {
+		hasElements = true
+		if !e {
+			return true
 		}
 	}
-	return true
+	return !hasElements
+}
+
+// AnyFalse returns whether there is a value set to false
+func AnyFalse(values ...bool) bool {
+	return AnyFalseSequence(slices.Values(values))
+}
+
+// AllSequence returns true if all items of the sequence are true.
+func AllSequence(seq iter.Seq[bool]) bool {
+	return !AnyFalseSequence(seq)
+}
+
+// All returns true if all items of the slice are true.
+func All(slice []bool) bool {
+	return AllSequence(slices.Values(slice))
 }
 
 // AllTrue returns whether all values are true.

utils/collection/conditions_test.go

@@ -25,6 +25,14 @@ func TestAnyTrue(t *testing.T) {
 	assert.True(t, AnyTrue(true, true, true, true, true, true, true, true, true, false, true, true, true, true, true, true, true, true, true, true))
 }
 
+func TestAnyFalse(t *testing.T) {
+	assert.True(t, AnyFalse())
+	assert.True(t, AnyFalse(false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false))
+	assert.True(t, AnyFalse(false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false))
+	assert.False(t, AnyFalse(true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true))
+	assert.True(t, AnyFalse(true, true, true, true, true, true, true, true, true, false, true, true, true, true, true, true, true, true, true, true))
+}
+
 func TestAll(t *testing.T) {
 	assert.False(t, All([]bool{}))
 	assert.False(t, All([]bool{false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false}))

utils/collection/search.go

@@ -5,10 +5,14 @@
 package collection
 
 import (
+	"iter"
 	"slices"
 	"strings"
 
+	"github.com/ARM-software/golang-utils/utils/commonerrors"
+	"github.com/ARM-software/golang-utils/utils/safecast"
 	mapset "github.com/deckarep/golang-set/v2"
+	"go.uber.org/atomic"
 )
 
 // Find looks for an element in a slice. If found it will
@@ -20,6 +24,22 @@ func Find(slice *[]string, val string) (int, bool) {
 	return FindInSlice(true, *slice, val)
 }
 
+// FindInSequence searches a collection for an element satisfying the predicate.
+func FindInSequence[E any](elements iter.Seq[E], predicate Predicate[E]) (int, bool) {
+	if elements == nil {
+		return -1, false
+	}
+	idx := atomic.NewUint64(0)
+	for e := range elements {
+		if predicate(e) {
+			return safecast.ToInt(idx.Load()), true
+		}
+		idx.Inc()
+	}
+
+	return -1, false
+}
+
 // FindInSlice finds if any values val are present in the slice and if so returns the first index.
 // if strict, it checks for an exact match; otherwise it discards whitespaces and case.
 func FindInSlice(strict bool, slice []string, val ...string) (int, bool) {
@@ -62,6 +82,46 @@ func UniqueEntries[T comparable](slice []T) []T {
 	return subSet.ToSlice()
 }
 
+// Unique returns all the unique values contained in a sequence.
+func Unique[T comparable](s iter.Seq[T]) []T {
+	return UniqueEntries(slices.Collect(s))
+}
+
+// Union returns the union of two slices (only unique values are returned).
+func Union[T comparable](slice1, slice2 []T) []T {
+	subSet := mapset.NewSet[T]()
+	_ = subSet.Append(slice1...)
+	_ = subSet.Append(slice2...)
+	return subSet.ToSlice()
+}
+
+// Intersection returns the intersection of two slices (only unique values are returned).
+func Intersection[T comparable](slice1, slice2 []T) []T {
+	subSet1 := mapset.NewSet[T]()
+	subSet2 := mapset.NewSet[T]()
+	_ = subSet1.Append(slice1...)
+	_ = subSet2.Append(slice2...)
+	return subSet1.Intersect(subSet2).ToSlice()
+}
+
+// Difference returns the Difference between slice1 and slice2 (only unique values are returned).
+func Difference[T comparable](slice1, slice2 []T) []T {
+	subSet1 := mapset.NewSet[T]()
+	subSet2 := mapset.NewSet[T]()
+	_ = subSet1.Append(slice1...)
+	_ = subSet2.Append(slice2...)
+	return subSet1.Difference(subSet2).ToSlice()
+}
+
+// SymmetricDifference returns the symmetric difference between slice1 and slice2 (only unique values are returned).
+func SymmetricDifference[T comparable](slice1, slice2 []T) []T {
+	subSet1 := mapset.NewSet[T]()
+	subSet2 := mapset.NewSet[T]()
+	_ = subSet1.Append(slice1...)
+	_ = subSet2.Append(slice2...)
+	return subSet1.SymmetricDifference(subSet2).ToSlice()
+}
+
 // AnyFunc returns whether there is at least one element of slice s for which f() returns true.
 func AnyFunc[S ~[]E, E any](s S, f func(E) bool) bool {
 	conditions := NewConditions(len(s))
@@ -73,17 +133,50 @@ func AnyFunc[S ~[]E, E any](s S, f func(E) bool) bool {
 
 type FilterFunc[E any] func(E) bool
 
+type Predicate[E any] = FilterFunc[E]
+
 // Filter returns a new slice that contains elements from the input slice which return true when they’re passed as a parameter to the provided filtering function f.
-func Filter[S ~[]E, E any](s S, f FilterFunc[E]) (result S) {
-	result = make(S, 0, len(s))
+func Filter[S ~[]E, E any](s S, f FilterFunc[E]) S {
+	return slices.Collect[E](FilterSequence[E](slices.Values(s), f))
+}
 
-	for i := range s {
-		if f(s[i]) {
-			result = append(result, s[i])
+// FilterSequence returns a new sequence that contains elements from the input sequence which return true when they’re passed as a parameter to the provided filtering function f.
+func FilterSequence[E any](s iter.Seq[E], f Predicate[E]) (result iter.Seq[E]) {
+	return func(yield func(E) bool) {
+		for v := range s {
+			if f(v) {
+				if !yield(v) {
+					return
+				}
+			}
 		}
 	}
+}
+
+// ForEachValues iterates over values and executes the passed function on each of them.
+func ForEachValues[E any](f func(E), values ...E) {
+	ForEach(values, f)
+}
+
+// ForEach iterates over elements and executes the passed function on each element.
+func ForEach[S ~[]E, E any](s S, f func(E)) {
+	_ = Each[E](slices.Values(s), func(e E) error {
+		f(e)
+		return nil
+	})
+}
 
-	return result
+// Each iterates over a sequence and executes the passed function against each element.
+// If passed func returns an error, the iteration stops and the error is returned, unless it is EOF.
+func Each[T any](s iter.Seq[T], f func(T) error) error {
+	for e := range s {
+		err := f(e)
+		if err != nil {
+			err = commonerrors.Ignore(err, commonerrors.ErrEOF)
+			return err
+		}
+	}
+	return nil
 }
 
 type MapFunc[T1, T2 any] func(T1) T2
@@ -95,15 +188,28 @@ func IdentityMapFunc[T any]() MapFunc[T, T] {
 	}
 }
 
-// Map creates a new slice and populates it with the results of calling the provided function on every element in input slice.
-func Map[T1 any, T2 any](s []T1, f MapFunc[T1, T2]) (result []T2) {
-	result = make([]T2, len(s))
+// MapSequence creates a new sequences and populates it with the results of calling the provided function on every element of the input sequence.
+func MapSequence[T1 any, T2 any](s iter.Seq[T1], f MapFunc[T1, T2]) iter.Seq[T2] {
+	return MapSequenceWithError[T1, T2](s, func(t1 T1) (T2, error) {
+		return f(t1), nil
+	})
+}
 
-	for i := range s {
-		result[i] = f(s[i])
+// MapSequenceWithError creates a new sequences and populates it with the results of calling the provided function on every element of the input sequence. If an error happens, the mapping stops.
+func MapSequenceWithError[T1 any, T2 any](s iter.Seq[T1], f MapWithErrorFunc[T1, T2]) iter.Seq[T2] {
+	return func(yield func(T2) bool) {
+		for v := range s {
+			mapped, subErr := f(v)
+			if subErr != nil || !yield(mapped) {
+				return
+			}
+		}
 	}
+}
 
-	return result
+// Map creates a new slice and populates it with the results of calling the provided function on every element in input slice.
+func Map[T1 any, T2 any](s []T1, f MapFunc[T1, T2]) []T2 {
+	return slices.Collect[T2](MapSequence[T1, T2](slices.Values(s), f))
 }
 
 // MapWithError creates a new slice and populates it with the results of calling the provided function on every element in input slice. If an error happens, the mapping stops and the error returned.
@@ -122,10 +228,32 @@ func MapWithError[T1 any, T2 any](s []T1, f MapWithErrorFunc[T1, T2]) (result []
 	return
 }
 
+// OppositeFunc returns the opposite of a FilterFunc.
+func OppositeFunc[E any](f FilterFunc[E]) FilterFunc[E] { return func(e E) bool { return !f(e) } }
+
 // Reject is the opposite of Filter and returns the elements of collection for which the filtering function f returns false.
 // This is functionally equivalent to slices.DeleteFunc but it returns a new slice.
 func Reject[S ~[]E, E any](s S, f FilterFunc[E]) S {
-	return Filter(s, func(e E) bool { return !f(e) })
+	return Filter(s, OppositeFunc[E](f))
+}
+
+// RejectSequence is the opposite of FilterSequence and returns the elements of collection for which the filtering function f returns false.
+func RejectSequence[E any](s iter.Seq[E], f FilterFunc[E]) iter.Seq[E] {
+	return FilterSequence(s, OppositeFunc[E](f))
+}
+
+// Reduce runs a reducer function f over all elements in the array, in ascending-index order, and accumulates them into a single value.
+func Reduce[T1, T2 any](s []T1, accumulator T2, f ReduceFunc[T1, T2]) T2 {
+	return ReducesSequence[T1, T2](slices.Values(s), accumulator, f)
+}
+
+// ReducesSequence runs a reducer function f over all elements of a sequence, in ascending-index order, and accumulates them into a single value.
+func ReducesSequence[T1, T2 any](s iter.Seq[T1], accumulator T2, f ReduceFunc[T1, T2]) (result T2) {
+	result = accumulator
+	for e := range s {
+		result = f(result, e)
+	}
+	return
 }
 
 func match[E any](e E, matches []FilterFunc[E]) *Conditions {
@@ -148,13 +276,14 @@ func MatchAll[E any](e E, matches ...FilterFunc[E]) bool {
 
 type ReduceFunc[T1, T2 any] func(T2, T1) T2
 
-// Reduce runs a reducer function f over all elements in the array, in ascending-index order, and accumulates them into a single value.
-func Reduce[T1, T2 any](s []T1, accumulator T2, f ReduceFunc[T1, T2]) (result T2) {
-	result = accumulator
-	for i := range s {
-		result = f(result, s[i])
-	}
-	return
+// AllFunc returns whether f returns true for all the elements of slice s.
+func AllFunc[S ~[]E, E any](s S, f func(E) bool) bool {
+	return AllTrueSequence(slices.Values(s), f)
+}
+
+// AllTrueSequence returns whether f returns true for all the elements in a sequence.
+func AllTrueSequence[E any](s iter.Seq[E], f func(E) bool) bool {
+	return AllSequence(MapSequence[E, bool](s, f))
 }
 
 // AnyEmpty returns whether there is one entry in the slice which is empty.
@@ -164,15 +293,6 @@ func AnyEmpty(strict bool, slice []string) bool {
 	return found
 }
 
-// AllFunc returns whether f returns true for all the elements of slice s.
-func AllFunc[S ~[]E, E any](s S, f func(E) bool) bool {
-	conditions := NewConditions(len(s))
-	for i := range s {
-		conditions.Add(f(s[i]))
-	}
-	return conditions.All()
-}
-
 // AllNotEmpty returns whether all elements of the slice are not empty.
 // If strict, then whitespaces are considered as empty strings
 func AllNotEmpty(strict bool, slice []string) bool {