findIndex method

int findIndex(
  1. bool test(
    1. E element
    )
)

find the first element index that satisfies the given predicate test.

Iterates through elements and returns the first element index to satisfy test.

Example:

final numbers = <int>[1, 2, 3, 5, 6, 7];
int result = numbers.findIndex((element) => element < 5); // 0
int result = numbers.findIndex((element) => element > 5); // 4
int result = numbers.findIndex((element) => element > 10); // -1

Stops iterating on the first matching element.

Implementation

int findIndex(bool Function(E element) test) {
  int index = -1;
  for (E element in this) {
    index++;
    if (test(element)) return index;
  }
  return 0;
}