ISO printf

8.16.0.4

ISO printf🔗ℹ

This module provides implementations of the ISO standard C printf family of procedures, based on their description in the OpenBSD manual.

procedure
(printf fmt arg ...) → void?
fmt : string?
arg : any/c

Prints the args to standard output according to the format string fmt.

The %n directive is not currently supported. The %q directive prints the eq-hash-code of a value in hex format. Directives typically fail gracefully on invalid or missing input, but malformed format strings may raise an error (eg. specifying a precision value twice).

Examples:

> (require iso-printf)
> (printf "hello\n")
hello
> (printf "%03d\n" 1)
001
> (printf "%04hd %04hd\n" 32767 16777215)
32767 -001
> (printf "%0*.*f\n" 12 3 1234567.89)
01234567.890
> (printf "%+.9g\n" 1234.456789)
+1234.45679

procedure
(eprintf fmt arg ...) → void?
fmt : string?
arg : any/c

Prints the args to standard error according to the format string fmt.

procedure
(sprintf fmt arg ...) → string?
fmt : string?
arg : any/c

Constructs a string by interpreting fmt against the given args.

procedure
(fprintf out fmt arg ...) → void?
  out : output-port?
  fmt : string?
  arg : any/c

Prints the args to out according to the format string fmt.