Joe Marshall  <jrm@ccs.neu.edu> wrote:
+---------------
| Pascal Costanza <costanza@web.de> writes:
| > ...so that an implementation of the language isn't actually required
| > to do extensive program analysis to determine all instances of tail
| > recursion. ...
| 
| Right.  It only needs to find the `obvious' ones.
+---------------

Specifically, it only needs to find the specific (sub)expressions
required by R5RS "3.5 Proper tail recursion":

	<URL:http://www.schemers.org/Documents/Standards/R5RS/HTML/
	     r5rs-Z-H-6.html#%_sec_3.5>

Though as it says there, an implementation *may* do more:

	Note: Implementations are allowed, but not required, to recognize
	that some non-tail calls, such as the call to H above, can be
	evaluated as though they were tail calls. In the example above,
	the LET expression could be compiled as a tail call to H.


-Rob

-----
Rob Warnock			<rpw3@rpw3.org>
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