Format a string and write it to a stream.
The format function takes a control string, formats according to the format directives embedded in the string, and then writes the result to the stream argument.
The format codes accepted by format are described in the Format Directives section.
sealed
| stream | An instance of <stream>. |
| control-string | An instance of <string>. |
| #rest args | Instances of <object>. The objects to substitute for the format fields in control-string. |