---
name: "CamlinternalFormatBasics"
section: "3o"
platform: "linux"
package: "ocaml"
version: "5.5.0-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/CamlinternalFormatBasics"
---

# CamlinternalFormatBasics(3o)

no description

## NAME

CamlinternalFormatBasics - no description

## Module

Module   CamlinternalFormatBasics

## Documentation

Module **CamlinternalFormatBasics**\
  :  **sig end**

*type padty* =\
  \| Left\
  \| Right\
  \| Zeros

*type int\_conv* =\
  \| Int\_d\
  \| Int\_pd\
  \| Int\_sd\
  \| Int\_i\
  \| Int\_pi\
  \| Int\_si\
  \| Int\_x\
  \| Int\_Cx\
  \| Int\_X\
  \| Int\_CX\
  \| Int\_o\
  \| Int\_Co\
  \| Int\_u\
  \| Int\_Cd\
  \| Int\_Ci\
  \| Int\_Cu

*type float\_flag\_conv* =\
  \| Float\_flag\_\
  \| Float\_flag\_p\
  \| Float\_flag\_s

*type float\_kind\_conv* =\
  \| Float\_f\
  \| Float\_e\
  \| Float\_E\
  \| Float\_g\
  \| Float\_G\
  \| Float\_F\
  \| Float\_h\
  \| Float\_H\
  \| Float\_CF

*type float\_conv* =  **float\_flag\_conv \*** **float\_kind\_conv**

*type char\_set* =  **string**

*type counter* =\
  \| Line\_counter\
  \| Char\_counter\
  \| Token\_counter

*type* **('a, 'b)** *padding* =\
  \| No\_padding **:** **('a0, 'a0) padding**\
  \| Lit\_padding **:** **padty \* int** **-\>** **('a1, 'a1) padding**\
  \| Arg\_padding **:** **padty** **-\>** **(int -\> 'a2, 'a2) padding**

*type pad\_option* =  **int option**

*type* **('a, 'b)** *precision* =\
  \| No\_precision **:** **('a0, 'a0) precision**\
  \| Lit\_precision **:** **int** **-\>** **('a1, 'a1) precision**\
  \| Arg\_precision **:** **(int -\> 'a2, 'a2) precision**

*type prec\_option* =  **int option**

*type* **('a, 'b, 'c)** *custom\_arity* =\
  \| Custom\_zero **:** **('a0, string, 'a0) custom\_arity**\
  \| Custom\_succ **:** **('a1, 'b0, 'c0) custom\_arity** **-\>** **('a1, 'x -\> 'b0, 'x -\> 'c0) custom\_arity**

*type block\_type* =\
  \| Pp\_hbox\
  \| Pp\_vbox\
  \| Pp\_hvbox\
  \| Pp\_hovbox\
  \| Pp\_box\
  \| Pp\_fits

*type formatting\_lit* =\
  \| Close\_box\
  \| Close\_tag\
  \| Break **of** **string \* int \* int**\
  \| FFlush\
  \| Force\_newline\
  \| Flush\_newline\
  \| Magic\_size **of** **string \* int**\
  \| Escaped\_at\
  \| Escaped\_percent\
  \| Scan\_indic **of** **char**

*type* **('a, 'b, 'c, 'd, 'e, 'f)** *formatting\_gen* =\
  \| Open\_tag **:** **('a0, 'b0, 'c0, 'd0, 'e0, 'f0) format6** **-\>** **('a0, 'b0, 'c0, 'd0, 'e0, 'f0) formatting\_gen**\
  \| Open\_box **:** **('a1, 'b1, 'c1, 'd1, 'e1, 'f1) format6** **-\>** **('a1, 'b1, 'c1, 'd1, 'e1, 'f1) formatting\_gen**

*type* **('a, 'b, 'c, 'd, 'e, 'f)** *fmtty* =  **('a, 'b, 'c, 'd, 'e, 'f, 'a, 'b, 'c, 'd, 'e, 'f)** **fmtty\_rel**

*type* **('a1, 'b1, 'c1, 'd1, 'e1, 'f1, 'a2, 'b2, 'c2, 'd2, 'e2, 'f2)** *fmtty\_rel* =\
  \| Char\_ty **:** **('a10, 'b10, 'c10, 'd10, 'e10, 'f10, 'a20, 'b20, 'c20, 'd20, 'e20, 'f20)** **fmtty\_rel** **-\>** **(char -\> 'a10, 'b10, 'c10, 'd10, 'e10, 'f10, char -\> 'a20, 'b20, 'c20, 'd20,** **'e20, 'f20)** **fmtty\_rel**\
  \| String\_ty **:** **('a11, 'b11, 'c11, 'd11, 'e11, 'f11, 'a21, 'b21, 'c21, 'd21, 'e21, 'f21)** **fmtty\_rel** **-\>** **(string -\> 'a11, 'b11, 'c11, 'd11, 'e11, 'f11, string -\> 'a21, 'b21, 'c21,** **'d21, 'e21, 'f21)** **fmtty\_rel**\
  \| Int\_ty **:** **('a12, 'b12, 'c12, 'd12, 'e12, 'f12, 'a22, 'b22, 'c22, 'd22, 'e22, 'f22)** **fmtty\_rel** **-\>** **(int -\> 'a12, 'b12, 'c12, 'd12, 'e12, 'f12, int -\> 'a22, 'b22, 'c22, 'd22,** **'e22, 'f22)** **fmtty\_rel**\
  \| Int32\_ty **:** **('a13, 'b13, 'c13, 'd13, 'e13, 'f13, 'a23, 'b23, 'c23, 'd23, 'e23, 'f23)** **fmtty\_rel** **-\>** **(int32 -\> 'a13, 'b13, 'c13, 'd13, 'e13, 'f13, int32 -\> 'a23, 'b23, 'c23,** **'d23, 'e23, 'f23)** **fmtty\_rel**\
  \| Nativeint\_ty **:** **('a14, 'b14, 'c14, 'd14, 'e14, 'f14, 'a24, 'b24, 'c24, 'd24, 'e24, 'f24)** **fmtty\_rel** **-\>** **(nativeint -\> 'a14, 'b14, 'c14, 'd14, 'e14, 'f14, nativeint -\> 'a24, 'b24,** **'c24, 'd24, 'e24, 'f24)** **fmtty\_rel**\
  \| Int64\_ty **:** **('a15, 'b15, 'c15, 'd15, 'e15, 'f15, 'a25, 'b25, 'c25, 'd25, 'e25, 'f25)** **fmtty\_rel** **-\>** **(int64 -\> 'a15, 'b15, 'c15, 'd15, 'e15, 'f15, int64 -\> 'a25, 'b25, 'c25,** **'d25, 'e25, 'f25)** **fmtty\_rel**\
  \| Float\_ty **:** **('a16, 'b16, 'c16, 'd16, 'e16, 'f16, 'a26, 'b26, 'c26, 'd26, 'e26, 'f26)** **fmtty\_rel** **-\>** **(float -\> 'a16, 'b16, 'c16, 'd16, 'e16, 'f16, float -\> 'a26, 'b26, 'c26,** **'d26, 'e26, 'f26)** **fmtty\_rel**\
  \| Bool\_ty **:** **('a17, 'b17, 'c17, 'd17, 'e17, 'f17, 'a27, 'b27, 'c27, 'd27, 'e27, 'f27)** **fmtty\_rel** **-\>** **(bool -\> 'a17, 'b17, 'c17, 'd17, 'e17, 'f17, bool -\> 'a27, 'b27, 'c27, 'd27,** **'e27, 'f27)** **fmtty\_rel**\
  \| Format\_arg\_ty **:** **('g, 'h, 'i, 'j, 'k, 'l) fmtty** **\* ('a18, 'b18, 'c18, 'd18, 'e18, 'f18, 'a28, 'b28, 'c28, 'd28, 'e28, 'f28)** **fmtty\_rel** **-\>** **(('g, 'h, 'i, 'j, 'k, 'l) format6 -\> 'a18, 'b18,** **'c18, 'd18, 'e18, 'f18,** **('g, 'h, 'i, 'j, 'k, 'l) format6 -\> 'a28, 'b28,** **'c28, 'd28, 'e28, 'f28)** **fmtty\_rel**\
  \| Format\_subst\_ty **:** **('g0, 'h0, 'i0, 'j0, 'k0, 'l0, 'g1, 'b19, 'c19, 'j1, 'd19, 'a19)** **fmtty\_rel** **\* ('g0, 'h0, 'i0, 'j0, 'k0, 'l0, 'g2, 'b29, 'c29, 'j2, 'd29, 'a29)** **fmtty\_rel** **\* ('a19, 'b19, 'c19, 'd19, 'e19, 'f19, 'a29, 'b29, 'c29, 'd29, 'e29, 'f29)** **fmtty\_rel** **-\>** **(('g0, 'h0, 'i0, 'j0, 'k0, 'l0) format6 -\> 'g1,** **'b19, 'c19, 'j1, 'e19, 'f19,** **('g0, 'h0, 'i0, 'j0, 'k0, 'l0) format6 -\> 'g2,** **'b29, 'c29, 'j2, 'e29, 'f29)** **fmtty\_rel**\
  \| Alpha\_ty **:** **('a110, 'b110, 'c110, 'd110, 'e110, 'f110, 'a210, 'b210, 'c210, 'd210, 'e210,** **'f210)** **fmtty\_rel** **-\>** **(('b110 -\> 'x -\> 'c110) -\> 'x -\> 'a110, 'b110, 'c110, 'd110, 'e110, 'f110,** **('b210 -\> 'x -\> 'c210) -\> 'x -\> 'a210, 'b210, 'c210, 'd210, 'e210, 'f210)** **fmtty\_rel**\
  \| Theta\_ty **:** **('a111, 'b111, 'c111, 'd111, 'e111, 'f111, 'a211, 'b211, 'c211, 'd211, 'e211,** **'f211)** **fmtty\_rel** **-\>** **(('b111 -\> 'c111) -\> 'a111, 'b111, 'c111, 'd111, 'e111, 'f111,** **('b211 -\> 'c211) -\> 'a211, 'b211, 'c211, 'd211, 'e211, 'f211)** **fmtty\_rel**\
  \| Any\_ty **:** **('a112, 'b112, 'c112, 'd112, 'e112, 'f112, 'a212, 'b212, 'c212, 'd212, 'e212,** **'f212)** **fmtty\_rel** **-\>** **('x0 -\> 'a112, 'b112, 'c112, 'd112, 'e112, 'f112, 'x0 -\> 'a212, 'b212, 'c212,** **'d212, 'e212, 'f212)** **fmtty\_rel**\
  \| Reader\_ty **:** **('a113, 'b113, 'c113, 'd113, 'e113, 'f113, 'a213, 'b213, 'c213, 'd213, 'e213,** **'f213)** **fmtty\_rel** **-\>** **('x1 -\> 'a113, 'b113, 'c113, ('b113 -\> 'x1) -\> 'd113, 'e113, 'f113,** **'x1 -\> 'a213, 'b213, 'c213, ('b213 -\> 'x1) -\> 'd213, 'e213, 'f213)** **fmtty\_rel**\
  \| Ignored\_reader\_ty **:** **('a114, 'b114, 'c114, 'd114, 'e114, 'f114, 'a214, 'b214, 'c214, 'd214, 'e214,** **'f214)** **fmtty\_rel** **-\>** **('a114, 'b114, 'c114, ('b114 -\> 'x2) -\> 'd114, 'e114, 'f114, 'a214, 'b214,** **'c214, ('b214 -\> 'x2) -\> 'd214, 'e214, 'f214)** **fmtty\_rel**\
  \| End\_of\_fmtty **:** **('f115, 'b115, 'c115, 'd115, 'd115, 'f115, 'f215, 'b215, 'c215, 'd215, 'd215,** **'f215)** **fmtty\_rel**

*type* **('a, 'b, 'c, 'd, 'e, 'f)** *fmt* =\
  \| Char **:** **('a0, 'b0, 'c0, 'd0, 'e0, 'f0) fmt** **-\>** **(char -\> 'a0, 'b0, 'c0, 'd0, 'e0, 'f0) fmt**\
  \| Caml\_char **:** **('a1, 'b1, 'c1, 'd1, 'e1, 'f1) fmt** **-\>** **(char -\> 'a1, 'b1, 'c1, 'd1, 'e1, 'f1) fmt**\
  \| String **:** **('x, string -\> 'a2) padding** **\* ('a2, 'b2, 'c2, 'd2, 'e2, 'f2) fmt** **-\>** **('x, 'b2, 'c2, 'd2, 'e2, 'f2) fmt**\
  \| Caml\_string **:** **('x0, string -\> 'a3) padding** **\* ('a3, 'b3, 'c3, 'd3, 'e3, 'f3) fmt** **-\>** **('x0, 'b3, 'c3, 'd3, 'e3, 'f3) fmt**\
  \| Int **:** **int\_conv** **\* ('x1, 'y) padding** **\* ('y, int -\> 'a4) precision** **\* ('a4, 'b4, 'c4, 'd4, 'e4, 'f4) fmt** **-\>** **('x1, 'b4, 'c4, 'd4, 'e4, 'f4) fmt**\
  \| Int32 **:** **int\_conv** **\* ('x2, 'y0) padding** **\* ('y0, int32 -\> 'a5) precision** **\* ('a5, 'b5, 'c5, 'd5, 'e5, 'f5) fmt** **-\>** **('x2, 'b5, 'c5, 'd5, 'e5, 'f5) fmt**\
  \| Nativeint **:** **int\_conv** **\* ('x3, 'y1) padding** **\* ('y1, nativeint -\> 'a6) precision** **\* ('a6, 'b6, 'c6, 'd6, 'e6, 'f6) fmt** **-\>** **('x3, 'b6, 'c6, 'd6, 'e6, 'f6) fmt**\
  \| Int64 **:** **int\_conv** **\* ('x4, 'y2) padding** **\* ('y2, int64 -\> 'a7) precision** **\* ('a7, 'b7, 'c7, 'd7, 'e7, 'f7) fmt** **-\>** **('x4, 'b7, 'c7, 'd7, 'e7, 'f7) fmt**\
  \| Float **:** **float\_conv** **\* ('x5, 'y3) padding** **\* ('y3, float -\> 'a8) precision** **\* ('a8, 'b8, 'c8, 'd8, 'e8, 'f8) fmt** **-\>** **('x5, 'b8, 'c8, 'd8, 'e8, 'f8) fmt**\
  \| Bool **:** **('x6, bool -\> 'a9) padding** **\* ('a9, 'b9, 'c9, 'd9, 'e9, 'f9) fmt** **-\>** **('x6, 'b9, 'c9, 'd9, 'e9, 'f9) fmt**\
  \| Flush **:** **('a10, 'b10, 'c10, 'd10, 'e10, 'f10) fmt** **-\>** **('a10, 'b10, 'c10, 'd10, 'e10, 'f10) fmt**\
  \| String\_literal **:** **string \* ('a11, 'b11, 'c11, 'd11, 'e11, 'f11) fmt** **-\>** **('a11, 'b11, 'c11, 'd11, 'e11, 'f11) fmt**\
  \| Char\_literal **:** **char \* ('a12, 'b12, 'c12, 'd12, 'e12, 'f12) fmt** **-\>** **('a12, 'b12, 'c12, 'd12, 'e12, 'f12) fmt**\
  \| Format\_arg **:** **pad\_option** **\* ('g, 'h, 'i, 'j, 'k, 'l) fmtty** **\* ('a13, 'b13, 'c13, 'd13, 'e13, 'f13) fmt** **-\>** **(('g, 'h, 'i, 'j, 'k, 'l) format6 -\> 'a13, 'b13,** **'c13, 'd13, 'e13, 'f13)** **fmt**\
  \| Format\_subst **:** **pad\_option** **\* ('g0, 'h0, 'i0, 'j0, 'k0, 'l0, 'g2, 'b14, 'c14, 'j2, 'd14, 'a14)** **fmtty\_rel** **\* ('a14, 'b14, 'c14, 'd14, 'e14, 'f14) fmt** **-\>** **(('g0, 'h0, 'i0, 'j0, 'k0, 'l0) format6 -\> 'g2,** **'b14, 'c14, 'j2, 'e14, 'f14)** **fmt**\
  \| Alpha **:** **('a15, 'b15, 'c15, 'd15, 'e15, 'f15) fmt** **-\>** **(('b15 -\> 'x7 -\> 'c15) -\> 'x7 -\> 'a15, 'b15, 'c15, 'd15, 'e15, 'f15)** **fmt**\
  \| Theta **:** **('a16, 'b16, 'c16, 'd16, 'e16, 'f16) fmt** **-\>** **(('b16 -\> 'c16) -\> 'a16, 'b16, 'c16, 'd16, 'e16, 'f16)** **fmt**\
  \| Formatting\_lit **:** **formatting\_lit** **\* ('a17, 'b17, 'c17, 'd17, 'e17, 'f17) fmt** **-\>** **('a17, 'b17, 'c17, 'd17, 'e17, 'f17) fmt**\
  \| Formatting\_gen **:** **('a18, 'b18, 'c18, 'd18, 'e18, 'f18) formatting\_gen** **\* ('f18, 'b18, 'c18, 'e18, 'e20, 'f20) fmt** **-\>** **('a18, 'b18, 'c18, 'd18, 'e20, 'f20) fmt**\
  \| Reader **:** **('a19, 'b19, 'c19, 'd19, 'e19, 'f19) fmt** **-\>** **('x8 -\> 'a19, 'b19, 'c19, ('b19 -\> 'x8) -\> 'd19, 'e19, 'f19)** **fmt**\
  \| Scan\_char\_set **:** **pad\_option \* char\_set** **\* ('a20, 'b20, 'c20, 'd20, 'e21, 'f21) fmt** **-\>** **(string -\> 'a20, 'b20, 'c20, 'd20, 'e21, 'f21) fmt**\
  \| Scan\_get\_counter **:** **counter** **\* ('a21, 'b21, 'c21, 'd21, 'e22, 'f22) fmt** **-\>** **(int -\> 'a21, 'b21, 'c21, 'd21, 'e22, 'f22) fmt**\
  \| Scan\_next\_char **:** **('a22, 'b22, 'c22, 'd22, 'e23, 'f23) fmt** **-\>** **(char -\> 'a22, 'b22, 'c22, 'd22, 'e23, 'f23) fmt**\
  \| Ignored\_param **:** **('a23, 'b23, 'c23, 'd23, 'y4, 'x9) ignored** **\* ('x9, 'b23, 'c23, 'y4, 'e24, 'f24) fmt** **-\>** **('a23, 'b23, 'c23, 'd23, 'e24, 'f24) fmt**\
  \| Custom **:** **('a24, 'x10, 'y5) custom\_arity \* (unit -\> 'x10)** **\* ('a24, 'b24, 'c24, 'd24, 'e25, 'f25) fmt** **-\>** **('y5, 'b24, 'c24, 'd24, 'e25, 'f25) fmt**\
  \| End\_of\_format **:** **('f26, 'b25, 'c25, 'e26, 'e26, 'f26) fmt**

List of format elements.

*type* **('a, 'b, 'c, 'd, 'e, 'f)** *ignored* =\
  \| Ignored\_char **:** **('a0, 'b0, 'c0, 'd0, 'd0, 'a0) ignored**\
  \| Ignored\_caml\_char **:** **('a1, 'b1, 'c1, 'd1, 'd1, 'a1) ignored**\
  \| Ignored\_string **:** **pad\_option** **-\>** **('a2, 'b2, 'c2, 'd2, 'd2, 'a2) ignored**\
  \| Ignored\_caml\_string **:** **pad\_option** **-\>** **('a3, 'b3, 'c3, 'd3, 'd3, 'a3) ignored**\
  \| Ignored\_int **:** **int\_conv \* pad\_option** **-\>** **('a4, 'b4, 'c4, 'd4, 'd4, 'a4) ignored**\
  \| Ignored\_int32 **:** **int\_conv \* pad\_option** **-\>** **('a5, 'b5, 'c5, 'd5, 'd5, 'a5) ignored**\
  \| Ignored\_nativeint **:** **int\_conv \* pad\_option** **-\>** **('a6, 'b6, 'c6, 'd6, 'd6, 'a6) ignored**\
  \| Ignored\_int64 **:** **int\_conv \* pad\_option** **-\>** **('a7, 'b7, 'c7, 'd7, 'd7, 'a7) ignored**\
  \| Ignored\_float **:** **pad\_option \* prec\_option** **-\>** **('a8, 'b8, 'c8, 'd8, 'd8, 'a8) ignored**\
  \| Ignored\_bool **:** **pad\_option** **-\>** **('a9, 'b9, 'c9, 'd9, 'd9, 'a9) ignored**\
  \| Ignored\_format\_arg **:** **pad\_option** **\* ('g, 'h, 'i, 'j, 'k, 'l) fmtty** **-\>** **('a10, 'b10, 'c10, 'd10, 'd10, 'a10) ignored**\
  \| Ignored\_format\_subst **:** **pad\_option** **\* ('a11, 'b11, 'c11, 'd11, 'e0, 'f0) fmtty** **-\>** **('a11, 'b11, 'c11, 'd11, 'e0, 'f0) ignored**\
  \| Ignored\_reader **:** **('a12, 'b12, 'c12, ('b12 -\> 'x) -\> 'd12, 'd12, 'a12)** **ignored**\
  \| Ignored\_scan\_char\_set **:** **pad\_option \* char\_set** **-\>** **('a13, 'b13, 'c13, 'd13, 'd13, 'a13) ignored**\
  \| Ignored\_scan\_get\_counter **:** **counter** **-\>** **('a14, 'b14, 'c14, 'd14, 'd14, 'a14) ignored**\
  \| Ignored\_scan\_next\_char **:** **('a15, 'b15, 'c15, 'd15, 'd15, 'a15) ignored**

*type* **('a, 'b, 'c, 'd, 'e, 'f)** *format6* =\
  \| Format **of** **('a, 'b, 'c, 'd, 'e, 'f) fmt \* string**

*val concat\_fmtty* :  **('g1, 'b1, 'c1, 'j1, 'd1, 'a1, 'g2, 'b2, 'c2, 'j2, 'd2, 'a2)** **fmtty\_rel -\>** **('a1, 'b1, 'c1, 'd1, 'e1, 'f1, 'a2, 'b2, 'c2, 'd2, 'e2, 'f2)** **fmtty\_rel -\>** **('g1, 'b1, 'c1, 'j1, 'e1, 'f1, 'g2, 'b2, 'c2, 'j2, 'e2, 'f2)** **fmtty\_rel**

*val erase\_rel* :  **('a, 'b, 'c, 'd, 'e, 'f, 'g, 'h, 'i, 'j, 'k, 'l)** **fmtty\_rel -\>** **('a, 'b, 'c, 'd, 'e, 'f) fmtty**

*val concat\_fmt* :  **('a, 'b, 'c, 'd, 'e, 'f) fmt -\>** **('f, 'b, 'c, 'e, 'g, 'h) fmt -\>** **('a, 'b, 'c, 'd, 'g, 'h) fmt**

*type neutral\_concat* = {\
  f :  **'a 'b 'c 'd 'e 'f.** **\[ \`Char of char \| \`String of string \] -\>** **('a, 'b, 'c, 'd, 'e, 'f) fmt -\>** **('a, 'b, 'c, 'd, 'e, 'f) fmt** ;\
  }

*val string\_concat\_map* :  **neutral\_concat -\>** **('a, 'b, 'c, 'd, 'e, 'f) fmt -\>** **('a, 'b, 'c, 'd, 'e, 'f) fmt**

Helper function for splitting format string and char literal.

**Since** 5.4