How to add number validation in Neos form?

Question

I have to validate a textbox in Neos form. I want to validate a number between 7 to 90.

Here is my code, but it is not working:

 type: 'TYPO3.Form:SingleLineText'
    identifier: liednummer
    label: 'Die Nummer meines Lieblingsliedes'
    validators:
      - identifier: 'TYPO3.Flow:NotEmpty'
      - identifier: 'TYPO3.Flow:NumberRange'
    properties:
      placeholder: 'Liednummer'
      validation:
        'TYPO3\Flow\Validation\Validator\NumberRangeValidator':
          minimum: 7
          maximum: 90
    defaultValue: ''

What is wrong? Empty is working, but number and number range is not working.

Answer 1

Quite old question, so you have probably solved that problem, but maybe it will help someone else:

type: 'TYPO3.Form:SingleLineText'
identifier: liednummer
label: 'Die Nummer meines Lieblingsliedes'
validators:
  -
    identifier: 'TYPO3.Flow:NumberRange'
    options:
      minimum: '8'
      maximum: '22'
  -
    identifier: 'TYPO3.Flow:NotEmpty'
properties:
  placeholder: 10
defaultValue: ''