<!-- is a valid comment delimiter in JavaScript, in Web browsers.
But is --> also a valid comment delimiter in JavaScript, in Web browsers?
--> console.log('is this commented out?')This is the relevant grammar, but I find it difficult to parse.
Edit: I now think it is a valid single line comment, per the information in this answer, but the information in that answer still leaves room for ambiguity for me, so I am leaving this question open.
My interpretation of this is that a line like --> comment will in fact work as a comment.
This can be interpreted as the string --> followed by a SingleLineCommentChars sequence, which fits the definition of an HTMLCloseComment. An HTMLCloseComment all by itself on a single line fits the definition of a SingleLineHTMLCloseComment, which is one of the valid forms of a Comment
This can be verified in ECMAScript parsers like esprima. An input of
<!-- open --> close // standard produces:
{ "type": "Program", "body": [], "sourceType": "script", "leadingComments": [ { "type": "Line", "value": " open", "range": [ 0, 9 ] }, { "type": "Line", "value": " close", "range": [ 10, 19 ] }, { "type": "Line", "value": " standard", "range": [ 20, 31 ] } ] } Of course, just because you can doesn't mean you should, particularly in this situation.
<!--and end with-->, what exactly is your question<!--begins a comment and-->ends a comment. There is no such thing as a "single line comment delimiter". See See stackoverflow.com/questions/3757051/…