isLatLong function
Checks if the string is a valid latitude,longitude pair.
Latitude must be in the range -90 to 90 and longitude in the range -180 to 180. The two values are separated by a comma.
Example:
isLatLong('40.7128,-74.0060'); // true
isLatLong('0,0'); // true
isLatLong('91,0'); // false (latitude out of range)
Implementation
bool isLatLong(String str) => _isLatLong(str);