Implemented the regular expression ~ and & operators.

This turns out to be easy to do in NFA land.
The complement of an NFA has exactly the same number
and configuration of states and transitions, except
that the states have an inverted meaning; and furthermore,
failed character transitions are routed to an extra
state (which in this impelmentation is permanently
allocated and shared by all regexes). The regex &
is implemented trivially using DeMorgan's.

Also, bugfix: regular expressions like A|B|C are allowed
now by the syntax, rather than constituting syntax error.
Previously, this would have been entered as (A|B)|C.

1 files changed, 1 insertions, 1 deletions

diff --git a/lib.h b/lib.h
index 6188fc83..b50c1075 100644
--- a/lib.h
+++ b/lib.h
@@ -208,7 +208,7 @@ extern val keyword_package, system_package, user_package;
 extern val null, t, cons_s, str_s, chr_s, num_s, sym_s, pkg_s, fun_s, vec_s;
 extern val stream_s, hash_s, lcons_s, lstr_s, cobj_s;
 extern val var_s, regex_s, set_s, cset_s, wild_s, oneplus_s;
-extern val zeroplus_s, optional_s, compound_s, or_s, quasi_s;
+extern val zeroplus_s, optional_s, compl_s, compound_s, or_s, and_s, quasi_s;
 extern val skip_s, trailer_s, block_s, next_s, freeform_s, fail_s, accept_s;
 extern val all_s, some_s, none_s, maybe_s, cases_s, collect_s, until_s, coll_s;
 extern val define_s, output_s, single_s, first_s, last_s, empty_s;