import Lean namespace DocGen4 open Lean System IO Lean.Elab.Term syntax (name := includeStr) "include_str" str : term @[termElab includeStr] def includeStrImpl : TermElab := λ stx expectedType? => do let str := stx[1].isStrLit?.get! let path := FilePath.mk str if ←path.pathExists then if ←path.isDir then throwError s!"{str} is a directory" else let content ← FS.readFile path return mkStrLit content else throwError s!"\"{str}\" does not exist as a file" end DocGen4