type Inspector … // New returns an Inspector for the specified syntax trees. func New(files []*ast.File) *Inspector { … } type event … // Preorder visits all the nodes of the files supplied to New in // depth-first order. It calls f(n) for each node n before it visits // n's children. // // The complete traversal sequence is determined by ast.Inspect. // The types argument, if non-empty, enables type-based filtering of // events. The function f is called only for nodes whose type // matches an element of the types slice. func (in *Inspector) Preorder(types []ast.Node, f func(ast.Node)) { … } // Nodes visits the nodes of the files supplied to New in depth-first // order. It calls f(n, true) for each node n before it visits n's // children. If f returns true, Nodes invokes f recursively for each // of the non-nil children of the node, followed by a call of // f(n, false). // // The complete traversal sequence is determined by ast.Inspect. // The types argument, if non-empty, enables type-based filtering of // events. The function f if is called only for nodes whose type // matches an element of the types slice. func (in *Inspector) Nodes(types []ast.Node, f func(n ast.Node, push bool) (proceed bool)) { … } // WithStack visits nodes in a similar manner to Nodes, but it // supplies each call to f an additional argument, the current // traversal stack. The stack's first element is the outermost node, // an *ast.File; its last is the innermost, n. func (in *Inspector) WithStack(types []ast.Node, f func(n ast.Node, push bool, stack []ast.Node) (proceed bool)) { … } // traverse builds the table of events representing a traversal. func traverse(files []*ast.File) []event { … }