go/src/go/ast/import.go

// SortImports sorts runs of consecutive import lines in import blocks in f.
// It also removes duplicate imports when it is possible to do so without data loss.
func SortImports(fset *token.FileSet, f *File) { … }

func lineAt(fset *token.FileSet, pos token.Pos) int { … }

func importPath(s Spec) string { … }

func importName(s Spec) string { … }

func importComment(s Spec) string { … }

// collapse indicates whether prev may be removed, leaving only next.
func collapse(prev, next Spec) bool { … }

type posSpan …

type cgPos …

func sortSpecs(fset *token.FileSet, f *File, specs []Spec) []Spec { … }