-- -*- text -*-

opt-grammar ::=
	{<(opt-production)>}*
;

end ::=
	~_
;

opt-production ::=
	:n <(opt)>:o => `(,n ,o)
;

opt ::=
	{:t <(t)>}
;

opt-inside :t ::=
	{:t1 =>(or (eq? t t1) (error 'expected t)) <(opt-inside t)>:xs} <(opt-inside t)>:ys
		=> (append xs ys)
|	<(opt)>:x <(opt-inside t)>:xs => (cons x xs)
|	=> '()
;

apply :prod (_*):args => `(apply ,prod ,@args);

or <(opt)>:o <(end)> => o;
or <(opt-inside 'or)>:os => (if (= (length os) 1) (car os) `(or ,@os));

seq <(opt)>:o <(end)> => o;
seq <(opt-inside 'seq)>:os => (if (= (length os) 1) (car os) `(seq ,@os));

nest <(opt)>:m <(end)> => `(nest ,m);
not <(opt)>:m <(end)> => `(not ,m);
follow <(opt)>:m <(end)> => `(follow ,m);
many <(opt)>:m <(end)> => `(many ,m);
many1 <(opt)>:m <(end)> => `(many1 ,m);
anything <(end)> => `(anything);
bind :n <(opt)>:m => `(bind ,n ,m);
action :exp => `(action ,exp);
exactly :datum => `(exactly ,datum);
sequence :exp => `(sequence ,exp);