prompt: What's the arr.splice here doing in this Typescript code?
  export function removeIfPresent<T>(arr: T[] | undefined, item: T) {
      if (!arr) {
          return;
      }
      const index = arr.indexOf(item);
      if (index !== -1) {
          arr.splice(index, 1);
      }
  }
chosen.role: system
chosen.content: A chat.
chosen.role: user
chosen.content: What's the arr.splice here doing in this Typescript code?
  export function removeIfPresent<T>(arr: T[] | undefined, item: T) {
      if (!arr) {
          return;
      }
      const index = arr.indexOf(item);
      if (index !== -1) {
          arr.splice(index, 1);
      }
  }
chosen.role: assistant
chosen.content: The call to Array#splice in this function removes the first instance of the provided item from the array if it is present in the array.
rejected.role: system
rejected.content: A chat.
rejected.role: user
rejected.content: What's the arr.splice here doing in this Typescript code?
  export function removeIfPresent<T>(arr: T[] | undefined, item: T) {
      if (!arr) {
          return;
      }
      const index = arr.indexOf(item);
      if (index !== -1) {
          arr.splice(index, 1);
      }
  }
rejected.role: assistant