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export interface GachaChoice<ItemType> {  result: ItemType;  chance: number;}
/** * Roll one item from a pool using linear search. Simple and great for smaller pools. * @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. * ``` */export function roll<ItemType>(  choices: GachaChoice<ItemType>[],  totalChance = 0,): ItemType {  let total = totalChance;  let i = 0;  if (totalChance === 0) {    while (i < choices.length) {      total += choices[i].chance;      i += 1;    }  }  const result = Math.random() * total;  let going = 0.0;  i = 0;  while (i < choices.length) {    going += choices[i].chance;    if (result < going) {      return choices[i].result;    }    i += 1;  }  return choices[Math.floor(Math.random() * choices.length)].result;}