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Module Js.Int

Bindings to functions in JavaScript's Number that deal with ints

Provides functions for inspecting and manipulating ints

type t = int;

If we use number, we need coerce to int32 by adding `|0`, otherwise `+0` can be wrong. Most JS API is float oriented, it may overflow int32 or comes with NAN

let toExponential: ?digits:t => t => string;

Formats an int using exponential (scientific) notation

digits specifies how many digits should appear after the decimal point. The value must be in the range [0, 20] (inclusive).

Returns a string representing the given value in exponential notation

The output will be rounded or padded with zeroes if necessary.

raises RangeError if digits is not in the range [0, 20] (inclusive)

ocaml
  Js.Int.toExponential 77 = "7.7e+1"
  Js.Int.toExponential ~digits:2 77 = "7.70e+1"
  Js.Int.toExponential ~digits:2 5678 = "5.68e+3"

see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/toExponential MDN

let toPrecision: ?digits:t => t => string;

Formats an int using some fairly arbitrary rules

digits specifies how many digits should appear in total. The value must between 1 and some 100.

Returns a string representing the given value in fixed-point or scientific notation

The output will be rounded or padded with zeroes if necessary.

toPrecision differs from Js.Float.toFixed in that the former will count all digits against the precision, while the latter will count only the digits after the decimal point. toPrecision will also use scientific notation if the specified precision is less than the number for digits before the decimal point.

raises RangeError if digits is not between 1 and 100.

ocaml
  Js.Int.toPrecision 123456789 = "123456789"
  Js.Int.toPrecision ~digits:2 123456789 = "1.2e+8"
  Js.Int.toPrecision ~digits:2 0 = "0.0"

see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/toPrecision MDN

let toString: ?radix:t => t => string;

Formats an int as a string

radix specifies the radix base to use for the formatted number. The value must be in the range [2, 36] (inclusive).

Returns a string representing the given value in fixed-point (usually)

raises RangeError if radix is not in the range [2, 36] (inclusive)

ocaml
  Js.Int.toString 123456789 = "123456789"
  Js.Int.toString ~radix:2 6 = "110"
  Js.Int.toString ~radix:16 3735928559 = "deadbeef"
  Js.Int.toString ~radix:36 123456 = "2n9c"

see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/toString MDN

let toFloat: t => float;
let equal: t => t => bool;
let max: t;
let min: t;