Function generator

modules/polaris/src/test/ts/atomic/api/ParrayGenerateTest.ts:9–19

(item: string, start: number)

UnitTest.test('api.PositionArray.generate', () => {
  const generator = (item: string, start: number): Optional<PArrayTestItem> => {
    const firstletter = item[0];
    if (firstletter === 'a') {
      return Optional.none();
    }
    return Optional.some({
      start,
      finish: start + item.length,
      item
    });
  };

  const check = (expected: string[], input: string[], start?: number) => {
    const result = PositionArray.generate(input, generator, start);