| bytes | Package bytes implements functions for the manipulation of byte slices. |
| errors | Package errors implements functions to manipulate errors. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| go/ast | Package ast declares the types used to represent syntax trees for Go packages. |
| go/parser | Package parser implements a parser for Go source files. |
| go/token | Package token defines constants representing the lexical tokens of the Go programming language and basic operations on tokens (printing, predicates). |
| golang.org/x/debug | Package debug provides the portable interface to a program being debugged. |
| golang.org/x/debug/arch | Package arch contains architecture-specific definitions. |
| golang.org/x/debug/dwarf | Package dwarf provides access to DWARF debugging information loaded from executable files, as defined in the DWARF 2.0 Standard at http://dwarfstd.org/doc/dwarf-2.0.0.pdf |
| golang.org/x/debug/elf | Package elf implements access to ELF object files. |
| golang.org/x/debug/macho | Package macho implements access to Mach-O object files. |
| golang.org/x/debug/server/protocol | Package protocol defines the types used to represent calls to the debug server. |
| math | Package math provides basic constants and mathematical functions. |
| math/big | Package big implements arbitrary-precision arithmetic (big numbers). |
| os | Package os provides a platform-independent interface to operating system functionality. |
| regexp | Package regexp implements regular expression search. |
| runtime | Package runtime contains operations that interact with Go's runtime system, such as functions to control goroutines. |
| strconv | Package strconv implements conversions to and from string representations of basic data types. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |
| sync | Package sync provides basic synchronization primitives such as mutual exclusion locks. |
| syscall | Package syscall contains an interface to the low-level operating system primitives. |
| time | Package time provides functionality for measuring and displaying time. |