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export type GachaChoice<ItemType> = {  result: ItemType;  chance: number;}
/** * Roll one item from a pool using linear search. Simple and great for one-time use pools. * Use `GachaMachine` if you will be picking multiple items from the same pool. * @param items List of items to roll from, each having a `result` and `chance`. * @param totalChance Total weight of the pool. * ```ts * const items = [ *   { result: "SSR cool character", chance: 1 }, *   { result: "Kinda rare character", chance: 3 }, *   { result: "Mob character", chance: 5 }, *   { result: "Mob character", chance: 5 }, *   { result: "Mob character", chance: 5 }, * ] * roll(items) // Rolls one item from the list of items * ``` * * ```ts * const items = [ *   { result: "SSR cool character", chance: 1 }, *   { result: "Kinda rare character", chance: 3 }, *   { result: "Mob character", chance: 5 }, *   { result: "Mob character", chance: 5 }, *   { result: "Mob character", chance: 5 }, * ] * roll(items, 19) // Rolls one item from the list of items, faster because the total chance is known. * ``` * @module */export function roll<ItemType>(  choices: ItemType[],  chances: number[],  totalChance?: number): ItemType;export function roll<ItemType>(  choices: GachaChoice<ItemType>[],  totalChance?: number): ItemType;export function roll<ItemType>(  choices: ItemType[] | GachaChoice<ItemType>[],  chanceArrOrTotalChance: number | number[] = 0,  totalChance = 0): ItemType {  const asArray = Array.isArray(chanceArrOrTotalChance);  let total = asArray ? totalChance : chanceArrOrTotalChance || 0;  if (typeof total !== "number") {    throw new TypeError(      `Invalid type for total chance. Expected 'undefined' or 'number', got '${typeof total}'`    );  }  let i = 0;  if (total === 0) {    while (i < choices.length) {      total += asArray        ? chanceArrOrTotalChance[i]        : (choices[i] as GachaChoice<ItemType>).chance;      i += 1;    }  }  const result = Math.random() * total;  let going = 0.0;  i = 0;  while (i < choices.length) {    going += asArray      ? chanceArrOrTotalChance[i]      : (choices[i] as GachaChoice<ItemType>).chance;    if (result < going) {      return asArray        ? (choices[i] as ItemType)        : (choices[i] as GachaChoice<ItemType>).result;    }    i += 1;  }  return asArray    ? (choices[Math.floor(Math.random() * choices.length)] as ItemType)    : (        choices[          Math.floor(Math.random() * choices.length)        ] as GachaChoice<ItemType>      ).result;}