22.2.1.3 Compiling Format Strings

A format string is essentially a program in a special-purpose language that performs printing, and that is interpreted by the function format. The formatter macro provides the efficiency of using a compiled function to do that same printing but without losing the textual compactness of format strings.

A format control is either a format string or a function that was returned by the the formatter macro.

• FORMAT-STRING-ARGUMENTS:SPECIFY