read-editor-version in Editors

• (read-editor-version in in-base parse-format? raise-errors?) -> boolean
     in : editor-stream-in% object
     in-base : editor-stream-in-base% object
     parse-format? : boolean
     raise-errors? = #t : boolean

  Reads version information from in-base, where in-base is the base for in. The version information parsed from in-base is recorded in in for later version-sensitive parsing. The procedure result is true if the version information was read successfully and if the version is supported.

  If parse-format? is true, then in-base is checked for an initial "WXME" format indicator. Use #f when "WXME" has been consumed already by format-dispatching code.

  If raise-errors? is true, then an error in reading triggers an exception, instead of a #f result.