%d not supported yet will be converted to a long string by joining stringified atoms using single spaces. then will be searched for %s placeholders {\,} which will be replaced by arguments {\$1} {\,} {\$2} {\,} {\$3} {\,} etc. {\,} sprintf style. (supports several %s unlike {[makefilename]).} make error messages FOR INTERNAL USE ONLY list of arguments for substituting into the %s placeholders. after substitution is done {\,} an error message will be generated with that text. the apparent source of the error will be the abstraction instance containing {[gf.error]} {\,} if applicable. this is what Find Last Error will find and highlight.