A value or a function that matches a specific day.

Matchers are passed to DayPicker via DayPickerBase.disabled, DayPickerBase.hidden]] | or [[DayPickerProps.selected and are used to determine if a day should get a Modifier.

Matchers can be of different types:

// will always match the day
const booleanMatcher: Matcher = true;

 // will match the today's date
const dateMatcher: Matcher = new Date();

// will match the days in the array
const arrayMatcher: Matcher = [new Date(2019, 1, 2), new Date(2019, 1, 4)];

// will match days after the 2nd of February 2019
const afterMatcher: DateAfter = { after: new Date(2019, 1, 2) };
 // will match days before the 2nd of February 2019 }
const beforeMatcher: DateBefore = { before: new Date(2019, 1, 2) };

// will match Sundays
const dayOfWeekMatcher: DayOfWeek = {
 dayOfWeek: 0
};

// will match the included days, except the two dates
const intervalMatcher: DateInterval = {
   after: new Date(2019, 1, 2),
   before: new Date(2019, 1, 5)
};

// will match the included days, including the two dates
const rangeMatcher: DateRange = {
   from: new Date(2019, 1, 2),
   to: new Date(2019, 1, 5)
};

// will match when the function return true
const functionMatcher: Matcher = (day: Date) => {
 return day.getMonth() === 2 // match when month is March
};