EmacsWiki: Regular ExpressionA regular expression (abbreviated “regexp” or sometimes just “re”) is a search-string with wildcards – and more. It is a pattern that is matched against the text to be searched. See Regexps. Examples: "alex"A plain string is a regular expression that matches the string exactly. The above regular expression matches “alex”. "alexa?"Some characters have special meanings in a regular expression. The q
正規表現の先読み・後読みを極める！ - あらびき日記
