selector interpreted as HTML

[gibson042]

#9521 and #6429 and probably others identify specific instances of a general problem: jQuery( strInput ) cannot reliably differentiate selectors from HTML.

 http://jsfiddle.net/C8dgG/

Looking for "<" past the first character creates vulnerabilities and confusing behavior on complex input.

quickExpr should be abandoned in favor of a simpler "parse as HTML if and only if there is a leading less-than" rule, with intentional parsing handled by the jQuery( "<div/>" ).html( strHtml ).contents() pattern.

[gibson042]

Also (for reference),  CSS lexical tokenization:

string	{string1}|{string2}
string1	\"([^\n\r\f\\"]|\\{nl}|{escape})*\"
string2	\'([^\n\r\f\\']|\\{nl}|{escape})*\'
escape	{unicode}|\\[^\n\r\f0-9a-f]
unicode	\\[0-9a-f]{1,6}(\r\n|[ \n\r\t\f])?