| errors | Package errors implements functions to manipulate errors. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| github.com/Knetic/govaluate | |
| github.com/bcicen/bfstree | |
| math | Package math provides basic constants and mathematical functions. |
| regexp | Package regexp implements regular expression search. |
| sort | Package sort provides primitives for sorting slices and user-defined collections. |
| 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. |