Standard Meta Characters

The Character Class

• Matches a list of characters.
• A caret (^) at the beginning of the list causes it to match only characters that are not in the list.
• The order of characters in the list doesn't matter.
• You may use a hyphen as a range delimiter, as in [a-z0-9], which is equivalent to \w
• If you want to match a caret, don't put it first.
• If you want to match a right bracket (]), don't put it last.
• Another option is to backslash these characters.
• Most characters loose their meta-ness inside square brackets.
• Since each character in the brackets is interpreted individually, it is meaningless to specify alternation with the vertical bar. A vertical bar is simply a vertical bar in a character class. So [fee|fie|foe] means the same as [feio|].