Random number generation

Random number generation for Tact smart contracts.

random

fun random(min: Int, max: Int): Int;

Generates and returns a new pseudo-random unsigned Int value x in the provided semi-closed interval: min $≤$ x $<$ max or min $≥$ x $>$ max, if both min and max are negative. Note, that max value is never included in the interval.

Usage examples:

random(42, 43); // 42, always
random(0, 42);  // 0-41, but never a 42

randomInt

fun randomInt(): Int;

Generates and returns a new pseudo-random unsigned $256$-bit Int value x.

The algorithm works as follows: if r is the old value of the random seed considered a $32$-byte array (by constructing the big-endian representation of an unsigned $256$-bit Int), then its sha512(r) is computed. The first $32$ bytes of this hash are stored as the new value r' of the random seed, and the remaining $32$ bytes are returned as the next random value x.

Usage example:

let allYourRandomBelongsToUs: Int = randomInt(); // ???, it's random :)