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Int

Signed integer numbers with infinite precision (also called big integers).

Most operations on integer numbers (e.g. addition) are available as built-in operators (e.g. -1 + 1). This module provides equivalent functions and Text conversion.

[Function form for higher-order use]

Several arithmetic and comparison functions (e.g. add, sub, equal, less, pow) are defined in this module to enable their use as first-class function values, which is not possible with operators like +, -, ==, etc., in Motoko. This allows you to pass these operations to higher-order functions such as map, foldLeft, or sort.

Import from the base library to use this module.

import Int "mo:base/Int";

Type Int​

type Int = Prim.Types.Int

Infinite precision signed integers.

Function abs​

func abs(x : Int) : Nat

Returns the absolute value of x.

Example:

Int.abs(-12) // => 12

Function toText​

func toText(x : Int) : Text

Converts an integer number to its textual representation. Textual representation do not contain underscores to represent commas.

Example:

Int.toText(-1234) // => "-1234"

Function min​

func min(x : Int, y : Int) : Int

Returns the minimum of x and y.

Example:

Int.min(2, -3) // => -3

Function max​

func max(x : Int, y : Int) : Int

Returns the maximum of x and y.

Example:

Int.max(2, -3) // => 2

Function hash​

func hash(i : Int) : Hash.Hash
[Deprecated function]

The function hash is deprecated. It computes a hash using only the least significant 32 bits of the Int, ignoring the rest. For large integers, this may lead to hash collisions. Use a bespoke hash function that considers all bits of the value instead.

Function hashAcc​

func hashAcc(h1 : Hash.Hash, i : Int) : Hash.Hash
[Deprecated function]

The function hashAcc is deprecated. It accumulates a hash using only the least significant 32 bits of the Int, ignoring other bits. This limits its effectiveness for large integers. Prefer using a custom hash function that processes the full integer input.

Function equal​

func equal(x : Int, y : Int) : Bool

Equality function for Int types. This is equivalent to x == y.

Example:

Int.equal(-1, -1); // => true

Example:

import Buffer "mo:base/Buffer";

let buffer1 = Buffer.Buffer<Int>(1);
buffer1.add(-3);
let buffer2 = Buffer.Buffer<Int>(1);
buffer2.add(-3);
Buffer.equal(buffer1, buffer2, Int.equal) // => true

Function notEqual​

func notEqual(x : Int, y : Int) : Bool

Inequality function for Int types. This is equivalent to x != y.

Example:

Int.notEqual(-1, -2); // => true

Function less​

func less(x : Int, y : Int) : Bool

"Less than" function for Int types. This is equivalent to x < y.

Example:

Int.less(-2, 1); // => true

Function lessOrEqual​

func lessOrEqual(x : Int, y : Int) : Bool

"Less than or equal" function for Int types. This is equivalent to x <= y.

Example:

Int.lessOrEqual(-2, 1); // => true

Function greater​

func greater(x : Int, y : Int) : Bool

"Greater than" function for Int types. This is equivalent to x > y.

Example:

Int.greater(1, -2); // => true

Function greaterOrEqual​

func greaterOrEqual(x : Int, y : Int) : Bool

"Greater than or equal" function for Int types. This is equivalent to x >= y.

Example:

Int.greaterOrEqual(1, -2); // => true

Function compare​

func compare(x : Int, y : Int) : {#less; #equal; #greater}

General-purpose comparison function for Int. Returns the Order ( either #less, #equal, or #greater) of comparing x with y.

Example:

Int.compare(-3, 2) // => #less

This function can be used as value for a high order function, such as a sort function.

Example:

import Array "mo:base/Array";
Array.sort([1, -2, -3], Int.compare) // => [-3, -2, 1]

Function neg​

func neg(x : Int) : Int

Returns the negation of x, -x .

Example:

Int.neg(123) // => -123

Function add​

func add(x : Int, y : Int) : Int

Returns the sum of x and y, x + y.

No overflow since Int has infinite precision.

Example:

Int.add(1, -2); // => -1

Example:

import Array "mo:base/Array";
Array.foldLeft([1, -2, -3], 0, Int.add) // => -4

Function sub​

func sub(x : Int, y : Int) : Int

Returns the difference of x and y, x - y.

No overflow since Int has infinite precision.

Example:

Int.sub(1, 2); // => -1

Example:

import Array "mo:base/Array";
Array.foldLeft([1, -2, -3], 0, Int.sub) // => 4

Function mul​

func mul(x : Int, y : Int) : Int

Returns the product of x and y, x * y.

No overflow since Int has infinite precision.

Example:

Int.mul(-2, 3); // => -6

Example:

import Array "mo:base/Array";
Array.foldLeft([1, -2, -3], 1, Int.mul) // => 6

Function div​

func div(x : Int, y : Int) : Int

Returns the signed integer division of x by y, x / y. Rounds the quotient towards zero, which is the same as truncating the decimal places of the quotient.

Traps when y is zero.

Example:

Int.div(6, -2); // => -3

Function rem​

func rem(x : Int, y : Int) : Int

Returns the remainder of the signed integer division of x by y, x % y, which is defined as x - x / y * y.

Traps when y is zero.

Example:

Int.rem(6, -4); // => 2

Function pow​

func pow(x : Int, y : Int) : Int

Returns x to the power of y, x ** y.

Traps when y is negative or y > 2 ** 32 - 1. No overflow since Int has infinite precision.

Example:

Int.pow(-2, 3); // => -8