func PrintType(fset *token.FileSet, decl ast.Decl, toURL func(string, string) string, topLevelDecls map[interface{}]bool) string
PrintType returns a string representation of the decl.
PrintType works by:
func Synopsis(fset *token.FileSet, n ast.Node, linkify func(string) string) string
Synopsis returns a one-line summary of the given input node.
func TopLevelDecls(pkg *doc.Package) map[interface{}]bool
TopLevelDecls returns the top level declarations in the package.