There are single and multi line comments in Javascript. All
Comment tokens are removed after the lexical phase.
A
SingleLineComment may not contain a
LineTerminator. Since any token is as long as possible, this means
SingleLineComment are parsed to the end of the line. The
LineTerminator at the end will not be part of the Comment though.
A
MultiLineComment that contains at least one
LineTerminator is not discarded from the token stream but replaced by a
LineTerminator Token instead.
Comments are allowed to contain any character except for a
LineTerminator. MultiLineComment tokens can not contain an embedded
*/ sequence. This is not affected by the greedy rule (take the longest sequence possible) because the productions are crafted thusly that it cannot occur.
In my personal oppionion, the production
MultiLineComment could be done much easier. Read
here for more information about that.