src/Pure/Thy/document_antiquotation.ML

   val thy_output_break: bool Config.T
   val thy_output_modes: string Config.T
   val trim_blanks: Proof.context -> string -> string
   val trim_lines: Proof.context -> string -> string
   val indent_lines: Proof.context -> string -> string
+  val prepare_lines: Proof.context -> string -> string
   val quote: Proof.context -> Pretty.T -> Pretty.T
   val indent: Proof.context -> Pretty.T -> Pretty.T
   val format: Proof.context -> Pretty.T -> string
   val output: Proof.context -> Pretty.T -> Output.output
   val print_antiquotations: bool -> Proof.context -> unit

 
 fun indent_lines ctxt =
   if Config.get ctxt thy_output_display then
     prefix_lines (Symbol.spaces (Config.get ctxt thy_output_indent))
   else I;
+
+fun prepare_lines ctxt = trim_lines ctxt #> indent_lines ctxt;
 
 
 (* output *)
 
 fun quote ctxt =