On Fri, 7 Nov 1997, Max Caines wrote:
> I am trying to construct a system filter expression to match a value in
> dollars, to look like this:
>
> if $h_Subject: matches "\\$[0-9]+"
>
> I have tried it with numbers of backslashes before the '$' ranging from
> zero to 4, and (in desperation) making it a character class (e.g.
> "[\\$][0-9]+"). Either it won't parse; or it does, but doesn't match a
> header like 'Make $150 now'. I can't work out from the documentation what
> the expression _should_ look like. Can anyone tell me?
The problems of multi-level escaping....
The regular expression you want is:
\$[0-9]+
Because its in an expanded string, you have to escape both \ and $. Thus
you get
\\\$[0-9]+
But you have also enclosed it in double quotes, in which \ is also
recognized as an escape character, so you have to put
"\\\\\\$[0-9]+"
Personally, I'd leave off the double quotes. It's bad enough as it is...
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