CamlinternalFormat(3) OCaml library CamlinternalFormat(3)

# [NAME](#NAME)

CamlinternalFormat - no description

# [Module](#Module)

Module CamlinternalFormat

# [Documentation](#Documentation)

Module **CamlinternalFormat**  
: **sig end**

*val is\_in\_char\_set* : **CamlinternalFormatBasics.char\_set -> char -> bool**

*val rev\_char\_set* : **CamlinternalFormatBasics.char\_set -> CamlinternalFormatBasics.char\_set**

*type mutable\_char\_set* = **bytes**

*val create\_char\_set* : **unit -> mutable\_char\_set**

*val add\_in\_char\_set* : **mutable\_char\_set -> char -> unit**

*val freeze\_char\_set* : **mutable\_char\_set -> CamlinternalFormatBasics.char\_set**

*type* **('a, 'b, 'c, 'd, 'e, 'f)** *param\_format\_ebb* =  
| Param\_format\_EBB **:** **('x -> 'a0, 'b0, 'c0, 'd0, 'e0, 'f0) CamlinternalFormatBasics.fmt** **->** **('a0, 'b0, 'c0, 'd0, 'e0, 'f0) param\_format\_ebb**

*val param\_format\_of\_ignored\_format* : **('a, 'b, 'c, 'd, 'y, 'x) CamlinternalFormatBasics.ignored ->** **('x, 'b, 'c, 'y, 'e, 'f) CamlinternalFormatBasics.fmt ->** **('a, 'b, 'c, 'd, 'e, 'f) param\_format\_ebb**

*type* **('b, 'c)** *acc\_formatting\_gen* =  
| Acc\_open\_tag **of** **('b, 'c) acc**  
| Acc\_open\_box **of** **('b, 'c) acc**

*type* **('b, 'c)** *acc* =  
| Acc\_formatting\_lit **of** **('b, 'c) acc * CamlinternalFormatBasics.formatting\_lit**  
| Acc\_formatting\_gen **of** **('b, 'c) acc** *** ('b, 'c) acc\_formatting\_gen**  
| Acc\_string\_literal **of** **('b, 'c) acc * string**  
| Acc\_char\_literal **of** **('b, 'c) acc * char**  
| Acc\_data\_string **of** **('b, 'c) acc * string**  
| Acc\_data\_char **of** **('b, 'c) acc * char**  
| Acc\_delay **of** **('b, 'c) acc * ('b -> 'c)**  
| Acc\_flush **of** **('b, 'c) acc**  
| Acc\_invalid\_arg **of** **('b, 'c) acc * string**  
| End\_of\_acc

*type* **('a, 'b)** *heter\_list* =  
| Cons **:** **'c * ('a0, 'b0) heter\_list** **->** **('c -> 'a0, 'b0) heter\_list**  
| Nil **:** **('b1, 'b1) heter\_list**

*type* **('b, 'c, 'e, 'f)** *fmt\_ebb* =  
| Fmt\_EBB **:** **('a, 'b0, 'c0, 'd, 'e0, 'f0) CamlinternalFormatBasics.fmt** **->** **('b0, 'c0, 'e0, 'f0) fmt\_ebb**

*val make\_printf* : **(('b, 'c) acc -> 'd) ->** **('b, 'c) acc ->** **('a, 'b, 'c, 'c, 'c, 'd) CamlinternalFormatBasics.fmt -> 'a**

*val make\_iprintf* : **('s -> 'f) ->** **'s -> ('a, 'b, 'c, 'd, 'e, 'f) CamlinternalFormatBasics.fmt -> 'a**

*val output\_acc* : **out\_channel ->** **(out\_channel, unit) acc -> unit**

*val bufput\_acc* : **Buffer.t -> (Buffer.t, unit) acc -> unit**

*val strput\_acc* : **Buffer.t -> (unit, string) acc -> unit**

*module Args :* **sig end**

*val make\_lprintf* : **(('b, 'c) acc -> 'f) ->** **('b, 'c) acc ->** **('a, 'b, 'c, 'c, 'c, 'f) CamlinternalFormatBasics.fmt ->** **('a, 'f) Args.t -> 'f**

*val type\_format* : **('x, 'b, 'c, 't, 'u, 'v) CamlinternalFormatBasics.fmt ->** **('a, 'b, 'c, 'd, 'e, 'f) CamlinternalFormatBasics.fmtty ->** **('a, 'b, 'c, 'd, 'e, 'f) CamlinternalFormatBasics.fmt**

*val fmt\_ebb\_of\_string* : **?legacy\_behavior:bool ->** **string -> ('b, 'c, 'e, 'f) fmt\_ebb**

*val format\_of\_string\_fmtty* : **string ->** **('a, 'b, 'c, 'd, 'e, 'f) CamlinternalFormatBasics.fmtty ->** **('a, 'b, 'c, 'd, 'e, 'f) CamlinternalFormatBasics.format6**

*val format\_of\_string\_format* : **string ->** **('a, 'b, 'c, 'd, 'e, 'f) CamlinternalFormatBasics.format6 ->** **('a, 'b, 'c, 'd, 'e, 'f) CamlinternalFormatBasics.format6**

*val char\_of\_iconv* : **CamlinternalFormatBasics.int\_conv -> char**

*val string\_of\_formatting\_lit* : **CamlinternalFormatBasics.formatting\_lit -> string**

*val string\_of\_fmtty* : **('a, 'b, 'c, 'd, 'e, 'f) CamlinternalFormatBasics.fmtty -> string**

*val string\_of\_fmt* : **('a, 'b, 'c, 'd, 'e, 'f) CamlinternalFormatBasics.fmt -> string**

*val open\_box\_of\_string* : **string -> int * CamlinternalFormatBasics.block\_type**

*val symm* : **('a1, 'b1, 'c1, 'd1, 'e1, 'f1, 'a2, 'b2, 'c2, 'd2, 'e2, 'f2)** **CamlinternalFormatBasics.fmtty\_rel ->** **('a2, 'b2, 'c2, 'd2, 'e2, 'f2, 'a1, 'b1, 'c1, 'd1, 'e1, 'f1)** **CamlinternalFormatBasics.fmtty\_rel**

*val trans* : **('a1, 'b1, 'c1, 'd1, 'e1, 'f1, 'a2, 'b2, 'c2, 'd2, 'e2, 'f2)** **CamlinternalFormatBasics.fmtty\_rel ->** **('a2, 'b2, 'c2, 'd2, 'e2, 'f2, 'a3, 'b3, 'c3, 'd3, 'e3, 'f3)** **CamlinternalFormatBasics.fmtty\_rel ->** **('a1, 'b1, 'c1, 'd1, 'e1, 'f1, 'a3, 'b3, 'c3, 'd3, 'e3, 'f3)** **CamlinternalFormatBasics.fmtty\_rel**

*val recast* : **('a1, 'b1, 'c1, 'd1, 'e1, 'f1) CamlinternalFormatBasics.fmt ->** **('a1, 'b1, 'c1, 'd1, 'e1, 'f1, 'a2, 'b2, 'c2, 'd2, 'e2, 'f2)** **CamlinternalFormatBasics.fmtty\_rel ->** **('a2, 'b2, 'c2, 'd2, 'e2, 'f2) CamlinternalFormatBasics.fmt**

2026-10-01 OCamldoc

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Document: CamlinternalFormat(3o) from ocaml 5.5.1-r1 (Chainguard OS)
Source: https://github.com/ocaml/ocaml