package go/ast
Walk traverses an AST in depth-first order: It starts by calling v.Visit(node); node must not be nil. If the visitor w returned by v.Visit(node) is not nil, Walk is invoked recursively with visitor w for each of the non-nil children of node, followed by a call of w.Visit(nil).
Golang go/ast.Walk() function usage examples
Example 1:
// walkFile walks the file's tree.
func (f *File) walkFile(name string, file *ast.File) {
Println("Checking file", name)
ast.Walk(f, file)
}
Example 2:
var f *ast.File
ast.Walk(visitFn(func(n ast.Node) {
sel, ok := n.(*ast.SelectorExpr)
}), f)
Reference :
http://golang.org/pkg/go/ast/#Walk
