.TH "Format_doc.Doc" 3 2025-07-04 OCamldoc "OCaml library"
.SH NAME
Format_doc.Doc \- Definitions and immutable API for composing documents
.SH Module
Module   Format_doc.Doc
.SH Documentation
.sp
Module
.BI "Doc"
 : 
.B sig end

.sp
Definitions and immutable API for composing documents

.sp

.sp
.sp

.PP
.SS Type definitions and core functions 

.PP
.I type box_type 
=
 | H
 | V
 | HV
 | HoV
 | B
 
.sp
Format box types

.sp
.I type stag 
= 
.B Format.stag

.sp

.sp
.I type element 
=
 | Text
.B of 
.B string
 | With_size
.B of 
.B int
 | Open_box
.B of {
 kind : 
.B box_type
;
 indent : 
.B int
;
 }
 | Close_box
 | Open_tag
.B of 
.B Format.stag
 | Close_tag
 | Open_tbox
 | Tab_break
.B of {
 width : 
.B int
;
 offset : 
.B int
;
 }
 | Set_tab
 | Close_tbox
 | Simple_break
.B of {
 spaces : 
.B int
;
 indent : 
.B int
;
 }
 | Break
.B of {
 fits : 
.B string * int * string
;
 breaks : 
.B string * int * string
;
 }
 | Flush
.B of {
 newline : 
.B bool
;
 }
 | Newline
 | If_newline
 | Deprecated
.B of 
.B (Format.formatter -> unit)
.I "  "
  (* Escape hatch: a 
.ft B
Format
.ft R
printer used to provide backward\-compatibility
for user\-defined printer (from the 
.ft B
#install_printer
.ft R
toplevel directive
for instance)\&.
 *)
 
.sp
Base formatting instruction recognized by 
.ft B
Format
.ft R


.sp
.I type t 

.sp
Immutable document type

.sp
.I type 
.B ('a, 'b)
.I fmt 
= 
.B ('a, t, t, 'b) format4

.sp

.sp
.I type printer0 
= 
.B t -> t

.sp

.sp
.I type 
.B 'a
.I printer 
= 
.B 'a -> printer0

.sp

.sp

.I val empty 
: 
.B t
.sp
Empty document

.sp

.I val format 
: 
.B Format.formatter -> t -> unit
.sp

.ft B
format ppf doc
.ft R
sends the format instruction of 
.ft B
doc
.ft R
to the Format\&'s
formatter 
.ft B
doc
.ft R
\&.

.sp

.I val fold 
: 
.B ('acc -> element -> 'acc) -> 'acc -> t -> 'acc
.sp
Fold over a document as a sequence of instructions

.sp

.I val msg 
: 
.B ('a, t) fmt -> 'a
.sp

.ft B
Format_doc\&.Doc\&.msg
.ft R
and 
.ft B
Format_doc\&.Doc\&.kmsg
.ft R
produce a document from a format string and its
argument

.sp

.I val kmsg 
: 
.B (t -> 'b) -> ('a, 'b) fmt -> 'a
.sp

.sp

.I val printf 
: 
.B ('a, printer0) fmt -> 'a
.sp

.ft B
Format_doc\&.Doc\&.printf
.ft R
and 
.ft B
Format_doc\&.Doc\&.kprintf
.ft R
produce a printer from a format string and its
argument

.sp

.I val kprintf 
: 
.B (t -> 'b) ->
.B   ('a, t -> 'b) fmt -> 'a
.sp

.sp

.I val open_box 
: 
.B box_type -> int -> printer0
.sp
The functions below mirror 
.ft B
Format
.ft R
printers, without the 
.ft B
pp_print_
.ft R
prefix naming convention

.sp

.I val close_box 
: 
.B printer0
.sp

.sp

.I val text 
: 
.B string printer
.sp

.sp

.I val string 
: 
.B string printer
.sp

.sp

.I val bytes 
: 
.B bytes printer
.sp

.sp

.I val with_size 
: 
.B int printer
.sp

.sp

.I val int 
: 
.B int printer
.sp

.sp

.I val float 
: 
.B float printer
.sp

.sp

.I val char 
: 
.B char printer
.sp

.sp

.I val bool 
: 
.B bool printer
.sp

.sp

.I val space 
: 
.B printer0
.sp

.sp

.I val cut 
: 
.B printer0
.sp

.sp

.I val break 
: 
.B spaces:int -> indent:int -> printer0
.sp

.sp

.I val custom_break 
: 
.B fits:string * int * string ->
.B   breaks:string * int * string -> printer0
.sp

.sp

.I val force_newline 
: 
.B printer0
.sp

.sp

.I val if_newline 
: 
.B printer0
.sp

.sp

.I val flush 
: 
.B printer0
.sp

.sp

.I val force_stop 
: 
.B printer0
.sp

.sp

.I val open_tbox 
: 
.B printer0
.sp

.sp

.I val set_tab 
: 
.B printer0
.sp

.sp

.I val tab 
: 
.B printer0
.sp

.sp

.I val tab_break 
: 
.B width:int -> offset:int -> printer0
.sp

.sp

.I val close_tbox 
: 
.B printer0
.sp

.sp

.I val open_tag 
: 
.B stag printer
.sp

.sp

.I val close_tag 
: 
.B printer0
.sp

.sp

.I val list 
: 
.B ?sep:printer0 ->
.B   'a printer -> 'a list printer
.sp

.sp

.I val iter 
: 
.B ?sep:printer0 ->
.B   iter:(('a -> unit) -> 'b -> unit) ->
.B   'a printer -> 'b printer
.sp

.sp

.I val array 
: 
.B ?sep:printer0 ->
.B   'a printer -> 'a array printer
.sp

.sp

.I val seq 
: 
.B ?sep:printer0 ->
.B   'a printer -> 'a Seq.t printer
.sp

.sp

.I val option 
: 
.B ?none:printer0 ->
.B   'a printer -> 'a option printer
.sp

.sp

.I val result 
: 
.B ok:'a printer ->
.B   error:'e printer ->
.B   ('a, 'e) result printer
.sp

.sp

.I val either 
: 
.B left:'a printer ->
.B   right:'b printer ->
.B   ('a, 'b) Either.t printer
.sp

.sp

.PP
.SS Alignment functions 

.PP

.I val align_prefix 
: 
.B (t * int) list -> t list
.sp
Align the right side of one 
.ft B
"@{<ralign>\&.\&.\&.@}"
.ft R
tag box by inserting
spaces at the beginning of boxes\&. Those function do nothing if the tag box
appears after a break hint\&.

.sp

.I val align_prefix2 
: 
.B t * int ->
.B   t * int -> t * t
.sp

.sp