update to go1.20 unsafe

unsafe/conversions.go

@@ -1,3 +1,5 @@
+//go:build !go1.20
+
 package unsafeext
 
 import (

unsafe/conversions_go121.go

@@ -0,0 +1,21 @@
+//go:build go1.20
+
+package unsafeext
+
+import (
+	"unsafe"
+)
+
+// BytesToString converts an array of bytes into a string without allocating.
+// The byte slice passed to this function is not to be used after this call as it's unsafe; you have been warned.
+func BytesToString(b []byte) string {
+	return unsafe.String(unsafe.SliceData(b), len(b))
+}
+
+// StringToBytes converts an existing string into an []byte without allocating.
+// The string passed to these functions is not to be used again after this call as it's unsafe; you have been warned.
+func StringToBytes(s string) (b []byte) {
+	d := unsafe.StringData(s)
+	b = unsafe.Slice(d, len(s))
+	return
+}