Module Pretty_utils

module Pretty_utils: sig .. end

Pretty-printer utilities.


null formatters

val null : Stdlib.Format.formatter

Prints nothing.

val nullprintf : ('a, Stdlib.Format.formatter, unit) Stdlib.format -> 'a

Discards the message and returns unit.

val with_null : (unit -> 'b) -> ('a, Stdlib.Format.formatter, unit, 'b) Stdlib.format4 -> 'a

Discards the message and call the continuation.

pretty-printing to a string

val sfprintf : ('a, Stdlib.Format.formatter, unit, string) Stdlib.format4 -> 'a
Deprecated.Silicon-20161101 use Format.asprintf

Equivalent to Format.asprintf. Used for compatibility with OCaml < 4.01.

val ksfprintf : (string -> 'b) ->
('a, Stdlib.Format.formatter, unit, 'b) Stdlib.format4 -> 'a

similar to Format.kfprintf, but the continuation is given the result string instead of a formatter.

val to_string : ?margin:int -> (Stdlib.Format.formatter -> 'a -> unit) -> 'a -> string

pretty-prints the supplied value into a string. margin is the maximal width of the box before a line-break is inserted. See Format.set_margin

separators

val pp_print_string_fill : Stdlib.Format.formatter -> string -> unit

transforms every space in a string in breakable spaces.

val escape_underscores : string -> string

pretty printers for standard types

type sformat = (unit, Stdlib.Format.formatter, unit) Stdlib.format 
type 'a formatter = Stdlib.Format.formatter -> 'a -> unit 
type ('a, 'b) formatter2 = Stdlib.Format.formatter -> 'a -> 'b -> unit 
val pp_list : ?pre:sformat ->
?sep:sformat ->
?last:sformat ->
?suf:sformat ->
?empty:sformat ->
'a formatter -> 'a list formatter

pretty prints a list. The optional arguments stands for

val pp_array : ?pre:sformat ->
?sep:sformat ->
?suf:sformat ->
?empty:sformat ->
(int, 'a) formatter2 -> 'a array formatter

pretty prints an array. The optional arguments stands for

val pp_iter : ?pre:sformat ->
?sep:sformat ->
?suf:sformat ->
(('a -> unit) -> 'b -> unit) ->
'a formatter -> 'b formatter

pretty prints any structure using an iterator on it. The argument pre (resp. suf) is output before (resp. after) the iterator is started (resp. has ended). The optional argument sep is output between two calls to the 'a formatter. Default: open a box for pre, close a box for suf, nothing for sep.

val pp_iter2 : ?pre:sformat ->
?sep:sformat ->
?suf:sformat ->
?between:sformat ->
(('key -> 'v -> unit) -> 'a -> unit) ->
'key formatter ->
'v formatter -> 'a formatter

pretty prints any map-like structure using an iterator on it. The argument pre (resp. suf) is output before (resp. after) the iterator is started (resp. has ended). The optional argument sep is output between two calls to the 'a formatter. The optional argument between is output between the key and the value. Default: open a box for pre, close a box for suf, nothing for sep, break-space for between.

val pp_opt : ?pre:sformat ->
?suf:sformat ->
?none:sformat ->
'a formatter -> 'a option formatter

pretty-prints an optional value. Prefix and suffix default to "@" and "@" respectively. If the value is None, pretty-print using none.

val pp_cond : ?pr_false:sformat ->
bool -> sformat formatter

pp_cond cond f s pretty-prints s if cond is true and the optional pr_false, which defaults to nothing, otherwise

val pp_pair : ?pre:sformat ->
?sep:sformat ->
?suf:sformat ->
'a formatter ->
'b formatter -> ('a * 'b) formatter

pp_pair ?pre ?sep ?suf pp_a pp_b (a,b) pretty prints the pair (a,b), using the pretty printers pp_a and pp_b, with optional prefix/separator/suffix, whose default values are:

val pp_flowlist : ?left:sformat ->
?sep:sformat ->
?right:sformat ->
'a formatter -> 'a list formatter
val pp_blocklist : ?left:sformat ->
?right:sformat ->
'a formatter -> 'a list formatter
val pp_open_block : Stdlib.Format.formatter ->
('a, Stdlib.Format.formatter, unit) Stdlib.format -> 'a
val pp_close_block : Stdlib.Format.formatter ->
('a, Stdlib.Format.formatter, unit) Stdlib.format -> 'a
val pp_trail : 'a formatter -> 'a formatter

pretty-prints its contents inside an '(** ... **)' horizontal block trailed with '*'

Description Lists (margins)

type align = [ `Center | `Left | `Right ] 
val pp_items : ?align:align ->
?margin:int ->
?min:int ->
?max:int ->
title:('a -> string) ->
iter:(('a -> unit) -> unit) ->
?pp_title:string formatter ->
pp_item:(string formatter -> 'a formatter) ->
Stdlib.Format.formatter -> unit

Prints a collection of elements, with the possibility of aligning titles with each others.

The collection of 'a to print is provided by iterator ~iter which is called twice: one for computing the maximal size of titles, obtained via function ~title for each item. The second pass pretty-print each item using ~pp_item pp where the passed pp printer can be used to pretty-print titles with alignment.

A typical usage for printing values, a list of (string*int) items:

      pp_items
        ~title:(fun (a,_) -> a)
        ~iter:(fun f -> List.iter f values)
        ~pp_title:(fun fmt a -> Format.fprintf fmt "%s:" a)
        ~pp_item:(fun pp fmt (a,n) -> Format.fprintf fmt "%a %d@\n" pp a n)
        fmt
    

Alignment of titles can be centered, right or left justified. This is rendered by adding spaces around each title. A min and max size can also be specified and a margin can be added to all title sizes. Titles will be truncated if necessary.

The pretty-printer for titles will render each (possibly truncated) title with ~pp_title. Surrounding spaces are not printed via ~pp_title.

The (optional) parameters have the following meaning:

There is also a low-level API to this feature, provided by Pretty_utils.marger, Pretty_utils.pp_margin and Pretty_utils.add_margin below.

type marger 

Margin accumulator (low-level API to pp_items).

val marger : unit -> marger

Create an empty marger

val add_margin : marger -> ?margin:int -> ?min:int -> ?max:int -> string -> unit

Updates the marger with new text dimension. The marger width is updated with the width of the provided text. The optional parameters are used to adjust the text width as follows:

val pp_margin : ?align:align ->
?pp:string formatter ->
marger -> string formatter

Prints a text with margins wrt to marger. If the text does not fit the marger, it would be truncated and/or ellipsed.

Typical usage:

      begin
        (* first, collect title margins *)
        let m = marger () in
        List.iter (fun (a,_) -> add_margin m ~margins:2 a) data ;
        (* second, print aligned data *)
        List.iter
          (fun (a,d) -> Format.printf "[%a] %s@\n" (pp_margin m) a d)
          data ;
      end