looking for text searching code

[philg@zurich.ai.mit.edu (Philip Greenspun)]

I want some public-domain Lisp code that does the following:

1) searches for a fixed substring in a string, being smart about
newlines, etc.  Thus, in the previous sentence, the code would be able
to find "about newlines"

2) searches for a regular expression in a string

3) does boolean queries, LEXIS style, into strings, e.g. "foo AND bar
WITHIN 20 LINES OF baz"

Does anyone know of anything?

Thanks,
--

      -- Philip Greenspun

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