Merge pull request #3446 from Michael-S/no_tail_call_optimization_elimination

Add section on tail call optimization/elimination.

Author: JJ

doc/Language/haskell-to-p6.pod6

@@ -537,6 +537,20 @@ compare it to let/in and where constructs maybe?
 
 TODO
 
+=head1 Tail Call Optimization or Tail Call Elimination
+
+Haskell and many other functional programming languages use tail call optimization, also
+sometimes called tail tall elimination, to remove the stack overhead of some types
+of recursive function calls.
+
+There is nothing in the Raku language specification forbidding the implementation of this
+class of optimization, but no current implementation has it.
+
+Please note that many Haskell looping constructs use recursive function calls.  Haskell programs
+would encounter stack overflow errors more often without tail call optimization. The standard
+Raku looping constructs are not built on recursive function calls, which makes the feature
+less important.
+
 =begin comment
 
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