[Help-source-highlight] regexp in javascript.lang (3rd try!)

[gnombat]

Last time I suggested an ugly regexp definition for
javascript.lang to avoid matching /* */ comments:

http://lists.gnu.org/archive/html/help-source-highlight/2008-09/msg00000.html

On second thought (or third thought) I don't like this because it
matches cases where there are two division operators in a single
expression, such as:

document.write('<table><tr><td>25% = '+(25/100)+'</td></tr></table>');

Here is a proposed javascript.lang to fix these problems.  It does the
following:
* first check if the input matches a comment
* next check if it matches a division operator, which can occur only
after a number, an identifier, or certain symbols
* finally check if it matches a regular expression

Note that it is no longer based on the java.lang because the order of
the definitions is important.  (Hence, this would not work with 
source-highlight 2.10, where the matching algorithm was different, but 
does work with source-highlight 2.11.)

The disadvantages:
* it no longer reuses java.lang
* the division operator definitions are ugly
The advantages:
* it works in all possible cases (I hope)
* it simplifies the regexp definition

What do you think?

include "c_comment.lang"

keyword =
"abstract|break|case|catch|class|const|continue|debugger|default|delete|do|else|enum|export|extends|false|final|finally|for|function|goto|if|implements|in|instanceof|interface|native|new|null|private|protected|prototype|public|return|static|super|switch|synchronized|throw|throws|this|transient|true|try|typeof|var|volatile|while|with"

(symbol,normal,symbol) = `(\+\+|--|\)|\])(\s*)(/=?(?![*/]))`
(number,normal,symbol) =
`(0x[[:xdigit:]]+|(?:[[:digit:]]*\.)?[[:digit:]]+(?:[eE][+-]?[[:digit:]]+)?)(\s*)(/(?![*/]))`
(normal,symbol) = `([[:alpha:]$_][[:alnum:]$_]*\s*)(/=?(?![*/]))`

regexp = '/(\\.|[^*\\/])(\\.|[^\\/])*/[gim]*'

include "number.lang"

include "c_string.lang"

include "symbols.lang"

cbracket = "{|}"

include "function.lang"