fact: Fixpoint gtree_mem t (w : chromogram) {struct w} := match t, w with | GtreeNode t0 t1 t2 t3, s :: w' => gtree_mem (gram_symbol_rec t0 t1 t2 t3 s) w' | GtreeLeaf0, [:: Gpush] => true | GtreeLeaf1, [:: Gskip] => true | GtreeLeaf2, [:: Gpop0] => true | GtreeLeaf3, [:: Gpop1] => true | GtreeLeaf01, [:: Gpush] => true | GtreeLeaf01, [:: Gskip] => true | GtreeLeaf12, [:: Gskip] => true | GtreeLeaf12, [:: Gpop0] => true | GtreeLeaf13, [:: Gskip] => true | GtreeLeaf13, [:: Gpop1] => true | GtreeLeaf23, [:: Gpop0] => true | GtreeLeaf23, [:: Gpop1] => true | _, _ => false end.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq) fourcolor(color chromogram)