Named capture groups with NSRegularExpression

Question

Does NSRegularExpression support named capture groups? It doesn\'t look like it from the documentation, but I wanted to check before I explore alternative solut

Answer 1

Named grouping is not supported in iOS, all you can do as I see is to make use of Enum:

Enum:

typedef enum
{
    kDayGroup = 1,
    kMonthGroup,
    kYearGroup
} RegexDateGroupsSequence;

Sample Code:

NSString *string = @"07-12-2014";
NSError *error = NULL;
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"(\\d{2})\\-(\\d{2})\\-(\\d{4}|\\d{2})"
                                                                       options:NSRegularExpressionCaseInsensitive
                                                                         error:&error];

NSArray *matches = [regex matchesInString:string
                                  options:0
                                    range:NSMakeRange(0, [string length])];
for (NSTextCheckingResult *match in matches) {
    NSString *day = [string substringWithRange:[match rangeAtIndex:kDayGroup]];
    NSString *month = [string substringWithRange:[match rangeAtIndex:kMonthGroup]];
    NSString *year = [string substringWithRange:[match rangeAtIndex:kYearGroup]];


    NSLog(@"Day: %@, Month: %@, Year: %@", day, month, year);
}