diff options
Diffstat (limited to 'design/43651-type-parameters.md')
| -rw-r--r-- | design/43651-type-parameters.md | 13 |
1 files changed, 4 insertions, 9 deletions
diff --git a/design/43651-type-parameters.md b/design/43651-type-parameters.md index d280f59..ac9219b 100644 --- a/design/43651-type-parameters.md +++ b/design/43651-type-parameters.md @@ -1484,14 +1484,9 @@ var V1 = Double(MySlice{1}) We can do what we want by introducing a new type parameter. ``` -// SC constraints a type to be a slice of some type E. -type SC[E any] interface { - []E // non-interface type constraint element -} - // DoubleDefined returns a new slice that contains the elements of s, // doubled, and also has the same type as s. -func DoubleDefined[S SC[E], E constraints.Integer](s S) S { +func DoubleDefined[S ~[]E, E constraints.Integer](s S) S { // Note that here we pass S to make, where above we passed []E. r := make(S, len(s)) for i, v := range s { @@ -1536,8 +1531,8 @@ We create a mapping of known type arguments: We then unify each type parameter with a structural constraint with the single type in that constraint's type set. -In this case the structural constraint is `SC[E]` which has the single -type `[]E`, so we unify `S` with `[]E`. +In this case the structural constraint is `~[]E` which has the +structural type `[]E`, so we unify `S` with `[]E`. Since we already have a mapping for `S`, we then unify `[]E` with `MySlice`. As `MySlice` is defined as `[]int`, that associates `E` with `int`. @@ -1756,7 +1751,7 @@ type Unsettable int func F4() { // This call is INVALID. - nums := FromString2[Unsettable]([]string{"1", "2"}) + nums := FromStrings2[Unsettable]([]string{"1", "2"}) ... } ``` |