| cmd/go/internal/par | |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| golang.org/x/mod/module | Package module defines the module.Version type along with support code. |
| reflect | Package reflect implements run-time reflection, allowing a program to manipulate objects with arbitrary types. |
| sort | Package sort provides primitives for sorting slices and user-defined collections. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |
| sync | Package sync provides basic synchronization primitives such as mutual exclusion locks. |