[1/2] custodian: look up proofs in local universe as well

fn/func.go

@@ -130,6 +130,18 @@ func All[T any](xs []T, pred func(T) bool) bool {
 	return true
 }
 
+// AllMapItems returns true if the passed predicate returns true for all items
+// in the map.
+func AllMapItems[T any, K comparable](xs map[K]T, pred func(T) bool) bool {
+	for i := range xs {
+		if !pred(xs[i]) {
+			return false
+		}
+	}
+
+	return true
+}
+
 // Any returns true if the passed predicate returns true for any item in the
 // slice.
 func Any[T any](xs []T, pred func(T) bool) bool {
@@ -142,12 +154,30 @@ func Any[T any](xs []T, pred func(T) bool) bool {
 	return false
 }
 
+// AnyMapItem returns true if the passed predicate returns true for any item in
+// the map.
+func AnyMapItem[T any, K comparable](xs map[K]T, pred func(T) bool) bool {
+	for i := range xs {
+		if pred(xs[i]) {
+			return true
+		}
+	}
+
+	return false
+}
+
 // NotAny returns true if the passed predicate returns false for all items in
 // the slice.
 func NotAny[T any](xs []T, pred func(T) bool) bool {
 	return !Any(xs, pred)
 }
 
+// NotAnyMapItem returns true if the passed predicate returns false for all
+// items in the map.
+func NotAnyMapItem[T any, K comparable](xs map[K]T, pred func(T) bool) bool {
+	return !AnyMapItem(xs, pred)
+}
+
 // Count returns the number of items in the slice that match the predicate.
 func Count[T any](xs []T, pred func(T) bool) int {
 	var count int
@@ -161,6 +191,20 @@ func Count[T any](xs []T, pred func(T) bool) int {
 	return count
 }
 
+// CountMapItems returns the number of items in the map that match the
+// predicate.
+func CountMapItems[T any, K comparable](xs map[K]T, pred func(T) bool) int {
+	var count int
+
+	for i := range xs {
+		if pred(xs[i]) {
+			count++
+		}
+	}
+
+	return count
+}
+
 // First returns the first item in the slice that matches the predicate, or an
 // error if none matches.
 func First[T any](xs []*T, pred func(*T) bool) (*T, error) {

fn/iter.go

@@ -7,10 +7,8 @@ package fn
 // This function can be used instead of the normal range loop to ensure that a
 // loop scoping bug isn't introduced.
 func ForEachErr[T any](s []T, f func(T) error) error {
-	for _, item := range s {
-		item := item
-
-		if err := f(item); err != nil {
+	for i := range s {
+		if err := f(s[i]); err != nil {
 			return err
 		}
 	}
@@ -22,9 +20,17 @@ func ForEachErr[T any](s []T, f func(T) error) error {
 // This can be used to ensure that any normal for-loop don't run into bugs due
 // to loop variable scoping.
 func ForEach[T any](items []T, f func(T)) {
-	for _, item := range items {
-		item := item
-		f(item)
+	for i := range items {
+		f(items[i])
+	}
+}
+
+// ForEachMapItem is a generic implementation of a for-each (map with side
+// effects). This can be used to ensure that any normal for-loop don't run into
+// bugs due to loop variable scoping.
+func ForEachMapItem[T any, K comparable](items map[K]T, f func(T)) {
+	for i := range items {
+		f(items[i])
 	}
 }
 
@@ -38,6 +44,14 @@ func Enumerate[T any](items []T, f func(int, T)) {
 	}
 }
 
+// EnumerateMap is a generic enumeration function. The closure will be called
+// for each key and item in the passed-in map.
+func EnumerateMap[T any, K comparable](items map[K]T, f func(K, T)) {
+	for key := range items {
+		f(key, items[key])
+	}
+}
+
 // MakeSlice is a generic function shorthand for making a slice out of a set
 // of elements. This can be used to avoid having to specify the type of the
 // slice as well as the types of the elements.