function is_array_of_strings()

in src/TypeAssert.hack [34:42]

• 9 lines of code
• 2 McCabe index (conditional complexity)

function is_array_of_strings(mixed $value, string $field): varray<string> {
  invariant($value is Container<_>, '%s should be an array<string>', $field);
  $out = varray[];
  foreach ($value as $it) {
    invariant($it is string, '%s should be an array<string>', $field);
    $out[] = $it;
  }
  return $out;
}