| 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/token | Package token defines constants representing the lexical tokens of the Go programming language and basic operations on tokens (printing, predicates). |
| golang.org/x/tools/go/analysis | Package analysis defines the interface between a modular static analysis and an analysis driver program. |
| golang.org/x/tools/go/analysis/passes/inspect | Package inspect defines an Analyzer that provides an AST inspector (golang.org/x/tools/go/ast/inspector.Inspector) for the syntax trees of a package. |
| honnef.co/go/tools/analysis/code | Package code answers structural and type questions about Go code. |
| honnef.co/go/tools/analysis/lint | Package lint provides abstractions on top of go/analysis. |
| honnef.co/go/tools/analysis/report | |
| strconv | Package strconv implements conversions to and from string representations of basic data types. |
| unicode | Package unicode provides data and functions to test some properties of Unicode code points. |
| unicode/utf8 | Package utf8 implements functions and constants to support text encoded in UTF-8. |