diff options
Diffstat (limited to 'stdlib/printf.mli')
| -rw-r--r-- | stdlib/printf.mli | 42 |
1 files changed, 24 insertions, 18 deletions
diff --git a/stdlib/printf.mli b/stdlib/printf.mli index 797a354dd0..942ec49b05 100644 --- a/stdlib/printf.mli +++ b/stdlib/printf.mli @@ -20,7 +20,7 @@ val fprintf : out_channel -> ('a, out_channel, unit) format -> 'a [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 + The format string 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 arguments. @@ -31,60 +31,66 @@ val fprintf : out_channel -> ('a, out_channel, unit) format -> 'a In short, a conversion specification consists in the [%] character, followed by optional modifiers and a type which is made of one or - two characters. The types and their meanings are: + two characters. - - [d], [i], [n], [l], [L], or [N]: convert an integer argument to - signed decimal. - - [u]: convert an integer argument to unsigned decimal. + The types and their meanings are: + + - [d], [i]: convert an integer argument to signed decimal. + - [u], [n], [l], [L], or [N]: convert an integer argument to + unsigned decimal. Warning: [n], [l], [L], and [N] are + used for [scanf], and should not be used for [printf]. - [x]: convert an integer argument to unsigned hexadecimal, using lowercase letters. - [X]: convert an integer argument to unsigned hexadecimal, using uppercase letters. - [o]: convert an integer argument to unsigned octal. - [s]: insert a string argument. - - [S]: insert a string argument in Caml syntax (double quotes, escapes). + - [S]: convert a string argument to OCaml syntax (double quotes, escapes). - [c]: insert a character argument. - - [C]: insert a character argument in Caml syntax (single quotes, escapes). + - [C]: convert a character argument to OCaml syntax (single quotes, escapes). - [f]: convert a floating-point argument to decimal notation, in the style [dddd.ddd]. - - [F]: convert a floating-point argument to Caml syntax ([dddd.] + - [F]: convert a floating-point argument to OCaml syntax ([dddd.] or [dddd.ddd] or [d.ddd e+-dd]). - [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] - - [b]: convert a boolean argument (for backward compatibility; do not - use in new programs). + - [b]: convert a boolean argument (deprecated; do not use in new + programs). - [ld], [li], [lu], [lx], [lX], [lo]: convert an [int32] argument to the format specified by the second letter (decimal, hexadecimal, etc). - [nd], [ni], [nu], [nx], [nX], [no]: convert a [nativeint] argument to the format specified by the second letter. - [Ld], [Li], [Lu], [Lx], [LX], [Lo]: convert an [int64] argument to the format specified by the second letter. - - [a]: user-defined printer. Takes two arguments and applies the + - [a]: user-defined printer. Take 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 inserted in the output of [fprintf] at the current point. - - [t]: same as [%a], but takes only one argument (with type + - [t]: same as [%a], but take only one argument (with type [out_channel -> unit]) and apply it to [outchan]. - [\{ fmt %\}]: convert a format string argument. The argument must have the same type as the internal format string [fmt]. - - [( fmt %)]: format string substitution. Takes a format string - argument and substitutes it to the internal format string [fmt] + - [( fmt %)]: format string substitution. Take a format string + argument and substitute it to the internal format string [fmt] to print following arguments. The argument must have the same type as the internal format string [fmt]. - [!]: take no argument and flush the output. - [%]: take no argument and output one [%] character. - - [,]: the no-op delimiter for conversion specifications. + - [\@]: take no argument and output one [\@] character. + - [,]: take no argument and do nothing. The optional [flags] are: - [-]: left-justify the output (default is right justification). - [0]: for numerical conversions, pad with zeroes instead of spaces. - - [+]: for numerical conversions, prefix number with a [+] sign if positive. - - space: for numerical conversions, prefix number with a space if positive. + - [+]: for signed numerical conversions, prefix number with a [+] + sign if positive. + - space: for signed numerical conversions, prefix number with a + space if positive. - [#]: request an alternate formatting style for numbers. The optional [width] is an integer indicating the minimal @@ -153,7 +159,7 @@ val kprintf : (string -> 'a) -> ('b, unit, string, 'a) format4 -> 'b;; (**/**) -(* For Caml system internal use only. Don't call directly. *) +(* For OCaml system internal use only. Don't call directly. *) module CamlinternalPr : sig |