Document Classes ⇒ clip current block (beamer)

[ltxsun]

Hi,
Is there a way to select the entire block (or exampleblock, etc.) in a clip? or even better, to only select the content part? I only know how to clip the bounding box, such as:

\path[clip] (current bounding box.north west) rectangle (current bounding box.south east);

Thanks!