Top-Down Operational Semantics (II)

Next: Some Results Up: CLP Program Execution Previous: Top-Down Operational Semantics (I)

Consider the program

$\begin{eqnarraystar}p(X+3, X) & \leftarrow & X < 3. \\ p(X+3, Y) & \leftarrow & X > 3, \; p(X, Y). \end{eqnarraystar}$

and the goal $\leftarrow p(5, X)$
A possible computation tree is:

$\begin{picture}(395,438)(160,360)\Large \thicklines \put(380,760){\vector(-2,-1... ...470,735){\makebox(0,0)[lb]{r}} \put(300,735){\makebox(0,0)[lb]{r}} \end{picture}$
Dotted rectangle: previous state was final as well

Last modification: Thu Oct 7 12:04:03 MEST 1999 <webmaster@clip.dia.fi.upm.es>