|
Written by Cisconet
|
1. Atom An atom is a single character, such as the following
| . |
Matches any single character
|
| |
Matches the beginning of the input string
|
| $ |
Matches the end of the input string
|
| \ |
Matches the character
|
| - |
Matches a comma (,), left brace ({), right brace (}), the beginning of the input string, the end of the input string, or a space.
|
2. Piece A piece is an atom followed by one of the following symbols
| * |
Matches 0 or more sequences of the atom
|
| + |
Matches 1 or more sequences of the atom
|
?
|
Matches the atom or the null string
|
3. Branch A branch is a 0 or more concatenated pieces
| a* |
Any occurrence of the letter "a", including none
|
| a+ |
At least one occurrence of the letter "a" should be present)
|
| ab?a |
This matches "aa" or "aba"
|
| _100_ |
Via AS100
|
| ^100$ |
Origin AS100
|
| ^100 .* |
Coming from AS100
|
| ^$ |
Originated from this AS
|
|
