diff options
Diffstat (limited to 'internal/util/unique.go')
| -rw-r--r-- | internal/util/unique.go | 30 |
1 files changed, 26 insertions, 4 deletions
diff --git a/internal/util/unique.go b/internal/util/unique.go index bad553d3f..68c1d1235 100644 --- a/internal/util/unique.go +++ b/internal/util/unique.go @@ -17,12 +17,23 @@ package util +// KeyBy creates a map of T->S, keyed by value returned from key func. +func KeyBy[S any, T comparable](in []S, key func(S) T) map[T]S { + if key == nil { + panic("nil func") + } + m := make(map[T]S, len(in)) + for _, v := range in { + m[key(v)] = v + } + return m +} + // Set represents a hashmap of only keys, // useful for deduplication / key checking. type Set[T comparable] map[T]struct{} -// ToSet creates a Set[T] from given values, -// noting that this does not maintain any order. +// ToSet creates a Set[T] from given values. func ToSet[T comparable](in []T) Set[T] { set := make(Set[T], len(in)) for _, v := range in { @@ -31,8 +42,19 @@ func ToSet[T comparable](in []T) Set[T] { return set } -// FromSet extracts the values from set to slice, -// noting that this does not maintain any order. +// ToSetFunc creates a Set[T] from input slice, keys provided by func. +func ToSetFunc[S any, T comparable](in []S, key func(S) T) Set[T] { + if key == nil { + panic("nil func") + } + set := make(Set[T], len(in)) + for _, v := range in { + set[key(v)] = struct{}{} + } + return set +} + +// FromSet extracts the values from set to slice. func FromSet[T comparable](in Set[T]) []T { out := make([]T, len(in)) var i int |