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Add a hacky Erlang VM printer #207

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 ./build/bin/re -k str -pl erl '^ab+c?.?[a-z]{2,3}$'
-module(fsm).
-export([main/1]).
main([String]) ->
	try fsm(start, list_to_binary(String))
	catch throw:fail ->
		io:format("failed~n"),
		halt(1);
	throw:{matched, N} ->
		io:format("matched ~b~n", [N]),
		halt(0)
	end.

fsm(start, <<_A,_B,_C, _Rest/binary>>) ->
	if
		
		_A /= 97 -> throw(fail);
		true -> ok
	end,
	if

		_B /= 98 -> throw(fail);
		true -> ok
	end,
	if

		_C =< 96 -> fsm(0, _Rest);
		_C == 97 -> fsm(4, _Rest);
		_C == 98 -> fsm(6, _Rest);
		_C == 99 -> fsm(8, _Rest);
		_C =< 122 -> fsm(4, _Rest)
	end;
fsm(0, <<>>) -> % e.g. "abA"
	throw({matched,3});
fsm(0=_State, <<_A,_Rest/binary>>) -> % e.g. "abA"
	 if		
		_A =< 96 -> throw(fail);
		_A > 122 -> throw(fail);
		true -> fsm(_State, _Rest)
	end;
fsm(1, <<>>) -> % e.g. "abAa"
	throw({matched,13});
fsm(1=_State, <<_A,_Rest/binary>>) -> % e.g. "abAa"
	 if		
		_A =< 96 -> throw(fail);
		_A > 122 -> throw(fail);
		true -> fsm(_State, _Rest)
	end;
fsm(2, <<>>) -> % e.g. "abaaa"
	throw({matched,9});
fsm(2=_State, <<_A,_Rest/binary>>) -> % e.g. "abaaa"
	 if		
		_A =< 96 -> throw(fail);
		_A > 122 -> throw(fail);
		true -> fsm(_State, _Rest)
	end;
fsm(3, <<>>) -> % e.g. "abaaaa"
	throw({matched,10});
fsm(3=_State, <<_A,_Rest/binary>>) -> % e.g. "abaaaa"
	 if		
		true -> throw(fail)
	end;
fsm(4, <<>>) -> % e.g. "aba"
	throw({matched,4});
fsm(4=_State, <<_A,_Rest/binary>>) -> % e.g. "aba"
	 if		
		_A =< 96 -> throw(fail);
		_A > 122 -> throw(fail);
		true -> fsm(_State, _Rest)
	end;
fsm(5, <<>>) -> % e.g. "abaa"
	throw({matched,8});
fsm(5=_State, <<_A,_Rest/binary>>) -> % e.g. "abaa"
	 if		
		_A =< 96 -> throw(fail);
		_A =< 122 -> fsm(2, _Rest);
		true -> throw(fail)
	end;
fsm(6, <<>>) -> % e.g. "abb"
	throw({matched,5});
fsm(6=_State, <<_A,_Rest/binary>>) -> % e.g. "abb"
	 if		
		_A =< 96 -> fsm(0, _Rest);
		_A == 97 -> fsm(7, _Rest);
		_A == 98 -> fsm(9, _Rest);
		_A == 99 -> fsm(10, _Rest);
		_A > 122 -> fsm(0, _Rest);
		true -> fsm(_State, _Rest)
	end;
fsm(7, <<>>) -> % e.g. "abca"
	throw({matched,7});
fsm(7=_State, <<_A,_Rest/binary>>) -> % e.g. "abca"
	 if		
		_A =< 96 -> throw(fail);
		_A =< 122 -> fsm(5, _Rest);
		true -> throw(fail)
	end;
fsm(8, <<>>) -> % e.g. "abc"
	throw({matched,6});
fsm(8=_State, <<_A,_Rest/binary>>) -> % e.g. "abc"
	 if		
		_A =< 96 -> fsm(0, _Rest);
		_A =< 122 -> fsm(7, _Rest);
		true -> fsm(0, _Rest)
	end;
fsm(9, <<>>) -> % e.g. "abbb"
	throw({matched,11});
fsm(9=_State, <<_A,_Rest/binary>>) -> % e.g. "abbb"
	 if		
		_A =< 96 -> fsm(0, _Rest);
		_A == 97 -> fsm(7, _Rest);
		_A == 98 -> fsm(9, _Rest);
		_A == 99 -> fsm(10, _Rest);
		_A =< 122 -> fsm(7, _Rest);
		true -> fsm(0, _Rest)
	end;
fsm(10, <<>>) -> % e.g. "abbc"
	throw({matched,12});
fsm(10=_State, <<_A,_Rest/binary>>) -> % e.g. "abbc"
	 if		
		_A =< 96 -> fsm(0, _Rest);
		_A =< 122 -> fsm(7, _Rest);
		true -> fsm(0, _Rest)
	end;
fsm(_, _) -> throw(fail).
; escript fsm.erl hello
failed
; escript fsm.erl abcdf
matched 8
; escript fsm.erl abd
matched 4
; escript fsm.erl ac
failed
; escript fsm.erl abcdefgh
matched 9

The code generator is really kind of terrible, could use some help dealing with the edge conditions better...

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