errors | Package errors implements functions to manipulate errors. |
fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
math/big | Package big implements arbitrary-precision arithmetic (big numbers). |
reflect | Package reflect implements run-time reflection, allowing a program to manipulate objects with arbitrary types. |
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. |
time | Package time provides functionality for measuring and displaying time. |
unicode/utf8 | Package utf8 implements functions and constants to support text encoded in UTF-8. |