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(***********************************************************************)
(* *)
(* Objective Caml *)
(* *)
(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
(* *)
(* Copyright 1996 Institut National de Recherche en Informatique et *)
(* en Automatique. All rights reserved. This file is distributed *)
(* under the terms of the GNU Library General Public License. *)
(* *)
(***********************************************************************)
(* $Id$ *)
(* Module [Printf]: formatting printing functions *)
val fprintf: out_channel -> ('a, out_channel, unit) format -> 'a
(* [fprintf outchan format arg1 ... argN] formats the arguments
[arg1] to [argN] according to the format string [format],
and outputs the resulting string on the channel [outchan].
The format is a character string which contains two types of
objects: plain characters, which are simply copied to the
output channel, and conversion specifications, each of which
causes conversion and printing of one argument.
Conversion specifications consist in the [%] character, followed
by optional flags and field widths, followed by one conversion
character. The conversion characters and their meanings are:
- [d] or [i]: convert an integer argument to signed decimal
- [u]: convert an integer argument to unsigned decimal
- [x]: convert an integer argument to unsigned hexadecimal,
using lowercase letters.
- [X]: convert an integer argument to unsigned hexadecimal,
using uppercase letters.
- [s]: insert a string argument
- [c]: insert a character argument
- [f]: convert a floating-point argument to decimal notation,
in the style [dddd.ddd]
- [e] or [E]: convert a floating-point argument to decimal notation,
in the style [d.ddd e+-dd] (mantissa and exponent)
- [g] or [G]: convert a floating-point argument to decimal notation,
in style [f] or [e], [E] (whichever is more compact)
- [b]: convert a boolean argument to the string [true] or [false]
- [a]: user-defined printer. Takes two arguments and apply the first
one to [outchan] (the current output channel) and to the second
argument. The first argument must therefore have type
[out_channel -> 'b -> unit] and the second ['b].
The output produced by the function is therefore inserted
in the output of [fprintf] at the current point.
- [t]: same as [%a], but takes only one argument (with type
[out_channel -> unit]) and apply it to [outchan].
- [%]: take no argument and output one [%] character.
- Refer to the C library [printf] function for the meaning of
flags and field width specifiers.
If too few arguments are provided, printing stops just
before converting the first missing argument. *)
val printf: ('a, out_channel, unit) format -> 'a
(* Same as [fprintf], but output on [stdout]. *)
val eprintf: ('a, out_channel, unit) format -> 'a
(* Same as [fprintf], but output on [stderr]. *)
val sprintf: ('a, unit, string) format -> 'a
(* Same as [fprintf], but instead of printing on an output channel,
return a string containing the result of formatting
the arguments. *)
val bprintf: Buffer.t -> ('a, Buffer.t, unit) format -> 'a
(* Same as [fprintf], but instead of printing on an output channel,
append the formatted arguments to the given extensible buffer
(see module [Buffer]). *)
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