Review of Regex Symbols
This chapter covered a lot of notation, so here’s a quick review of what you learned:
The
?matches zero or one of the preceding group.The
*matches zero or more of the preceding group.The
+matches one or more of the preceding group.The
{n}matches exactly n of the preceding group.The
{n,}matches n or more of the preceding group.The
{,m}matches 0 to m of the preceding group.The
{n,m}matches at least n and at most m of the preceding group.{n,m}?or*?or+?performs a nongreedy match of the preceding group.^spammeans the string must begin with spam.spam$means the string must end with spam.The
.matches any character, except newline characters.\d,\w, and\smatch a digit, word, or space character, respectively.\D,\W, and\Smatch anything except a digit, word, or space character, respectively.[abc]matches any character between the brackets (such as a, b, or c).[^abc]matches any character that isn’t between the brackets.