/*
 The test on treating open variables in patterns.
 
 Given a word e.w, we change all letters 'A' to 'D' in it and prepend a prefix
 consisting of letters 'C' and of the length equal to the length of e.x.

 MSCP-A determines that the prefix can not contain letters 'A', and brings it out from the loop
 changing letters 'A' to 'D'.
*/

/***********************************************/
/*           the input program                 */
/***********************************************/

$ENTRY Go {
    e.w = <F <H e.w> e.w>; 
}

F {
    e.x1 'A' e.x2 = e.x1 'D' <F e.x2>;
    e.Z = e.Z;
}


H {
 	= ;
	t.x e.y = 'C' <H e.y>;
}

/***********************************************************/
/*          the residual program (with ~UnAmb)             */
/***********************************************************/

/*
$ENTRY Go {
 e.x1 =  <F_0 () (e.x1) ()>;
}


F_12_0 {
 (e.x1) (e.x2) (e.x3 'A' e.x4) =  <F_12_0 (e.x1) (e.x2 e.x3 'D') (e.x4)>;
 (e.x1) (e.x2) (e.x3) =  e.x1 'D' e.x2 e.x3;
}


F_12_1 {
 (e.x1) (e.x2) (e.x3 'A' e.x4) =  <F_12_1 (e.x1) (e.x2 e.x3 'D') (e.x4)>;
 (e.x1) (e.x2) (e.x3) =  e.x1 'D' e.x2 e.x3;
}


F_0 {
 (e.x1) () ('A' e.x2) =  <F_12_0 (e.x1) () (e.x2)>;
 (e.x1) () (e.x2 'A' e.x3) =  <F_12_1 (e.x1 e.x2) () (e.x3)>;
 (e.x1) () (e.x2) =  e.x1 e.x2;
 (e.x1) (t.y1 e.x2) (e.x3) =  <F_0 (e.x1 'C') (e.x2) (e.x3 t.y1)>;
}
*/