// rrqforth.asm:	WORD p_execute,'EXECUTE',fasm

anchor:p_execute[]

=== Word: EXECUTE

....
Data stack: ( cfa -- )
....

"EXECUTE" is a function word that transfers the execution to the
indicated "Code Field Address", which typically is the CFA of an
RRQFORTH word with the CFA cell containing a jump address for the code
that implements the execution semnatics of the word.

The following execution semantics are predefined:

 * assembler implemented words constitute their own execution
   semantics;
   
 * <<p_doforth>> implements the FORTH machine. This treats the word
   content as a succession of cells that hold the cfa pointers for the
   words that make of the definition. As is customary in FORTH
   machines, the advance through that succession is provided by each
   word code ending making an explicit jump to its successor. The
   <<p_return_stack,RETURN-STACK>> serves as a call stack for tracking
   the nesting of FORTH executions by saving the "addresses" of the
   successor cells.

 * <<p_dodoes>> implements the variation of starting the FORTH
   execution somewhere within a definition rather than at the
   beginning.

 * <<p_dostring>>, <<p_dovalue>> and <<p_dovariable>> implement
   different common ways of using word content other the as FORTH
   definitions.