^start of line
Group sexe(?<sexe>[1-478]) 1-4one character from 1 (4910) to 4 (5210)
7the literal 7 (5510 / 678 / 3716)
8the literal 8 (5610 / 708 / 3816)
\s*?any whitespace character, repeated any number of times
Group annee(?<annee>[0-9]{2}) {2}matches exactly 2 characters from the set below:
0-9one character from 0 (4810) to 9 (5710)
\s*?any whitespace character, repeated any number of times
Group mois(?<mois>0[1-9]|1[0-2]|[2-3][0-9]|4[0-2]|[5-9][0-9]) 0the literal 0 (4810 / 608 / 3016)
1-9one character from 1 (4910) to 9 (5710)
1the literal 1 (4910 / 618 / 3116)
0-2one character from 0 (4810) to 2 (5010)
3rd Alternative[2-3][0-9] 2-3one character from 2 (5010) to 3 (5110)
0-9one character from 0 (4810) to 9 (5710)
4the literal 4 (5210 / 648 / 3416)
0-2one character from 0 (4810) to 2 (5010)
5th Alternative[5-9][0-9] 5-9one character from 5 (5310) to 9 (5710)
0-9one character from 0 (4810) to 9 (5710)
\s*?any whitespace character, repeated any number of times
Group departement(?<departement>2[ABab]|[0-9]{2}|9[7-8][0-9]) 2the literal 2 (5010 / 628 / 3216)
Athe literal A (6510 / 1018 / 4116) (case sensitive)
Bthe literal B (6610 / 1028 / 4216) (case sensitive)
athe literal a (9710 / 1418 / 6116) (case sensitive)
bthe literal b (9810 / 1428 / 6216) (case sensitive)
{2}matches exactly 2 characters from the set below:
0-9one character from 0 (4810) to 9 (5710)
3rd Alternative9[7-8][0-9] 9the literal 9 (5710 / 718 / 3916)
7-8one character from 7 (5510) to 8 (5610)
0-9one character from 0 (4810) to 9 (5710)
\s*?any whitespace character, repeated any number of times
Group commune(?<commune>[0-9]{3}|[0-9]{2}) \s*?any whitespace character, repeated any number of times
Group ordre(?<ordre>00[1-9]|0[1-9][0-9]|[1-9][0-9]{2}) \s*?any whitespace character, repeated any number of times
Group cle(?<cle>0[1-9]|[1-8][0-9]|9[0-7]) \s*?any whitespace character, repeated any number of times
$end of line
g modifier: global. Finds all matches instead of stopping after the first
m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string