question: public static String toString ( String d ) { int idx = 0 ; StringBuilder sb = new StringBuilder ( ) ; if ( d . charAt ( 0 ) == '(' ) { ++ idx ; sb . append ( "(" ) ; while ( idx < d . length ( ) && d . charAt ( idx ) != ')' ) { if ( idx != 1 ) sb . append ( ", " ) ; idx = Descriptor . toString ( d , idx , sb ) ; } if ( idx >= d . length ( ) ) throw new JaninoRuntimeException ( "Invalid descriptor \"" + d + "\"" ) ; sb . append ( ") => " ) ; ++ idx ; } Descriptor . toString ( d , idx , sb ) ; return sb . toString ( ) ; }
target:  Pretty-prints the given descriptor.