format

(format fmt args...)

Answers the Java-format string rendered: %s converts like str (nil spells "null", like String/valueOf), %b the boolean spelling, %d/%x/%X/ %o integers (checked), %c a character (checked), %f a float with optional width and precision, %% and %n themselves. The format string must be literal, since its directives translate at lowering time. Flags, %e/%g, dates, hashes and anything else are named refusals instead of wrong answers.