| 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/types | Package types declares the data types and implements the algorithms for type-checking of Go packages. |
| 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/ctrlflow | Package ctrlflow is an analysis that provides a syntactic control-flow graph (CFG) for the body of a function. |
| 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. |
| golang.org/x/tools/go/ast/inspector | Package inspector provides helper functions for traversal over the syntax trees of a package, including node filtering by type, and materialization of the traversal stack. |
| golang.org/x/tools/go/cfg | Package cfg constructs a simple control-flow graph (CFG) of the statements and expressions within a single function. |