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coclass->html
progid->html
3.4.2 Generating ActiveX HTML

(coclass->html name width height [size])  string?
  name : string?
  width : exact-integer?
  height : exact-integer?
  size : (one-of/c 'pixels 'percent) = 'pixels
(progid->html name width height [size])  string?
  name : string?
  width : exact-integer?
  height : exact-integer?
  size : (one-of/c 'pixels 'percent) = 'pixels
Returns a string containing HTML which when inserted into a document loads the COM object with the COM class or ProgID given by name. This procedure is suitable for placing ActiveX controls within complex HTML. The optional size argument gives an interpretation for the width and height arguments; by default, size is 'pixels, but may also be 'percent, indicating that the width and height are a fixed percentage of the document window size.