Update NEWS and docs for return
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NEWS
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NEWS
@ -16,6 +16,7 @@ Changes from 0.13.0
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* `get` is available as a function
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* new `comment` macro
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* support EDN `#_` syntax to discard the next term
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* `return` has been implemented as a special form
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[ Bug Fixes ]
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* Numeric literals are no longer parsed as symbols when followed by a dot
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@ -1469,6 +1469,38 @@ Given an empty collection, it returns an empty iterable.
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=> (list (rest []))
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[]
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return
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-------
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``return`` compiles to a :py:keyword:`return` statement. It exits the
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current function, returning its argument if provided with one or
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``None`` if not.
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.. code-block:: hy
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=> (defn f [x] (for [n (range 10)] (when (> n x) (return n))))
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=> (f 3.9)
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4
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Note that in Hy, ``return`` is necessary much less often than in Python,
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since the last form of a function is returned automatically. Hence, an
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explicit ``return`` is only necessary to exit a function early.
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.. code-block:: hy
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=> (defn f [x] (setv y 10) (+ x y))
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=> (f 4)
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14
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To get Python's behavior of returning ``None`` when execution reaches
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the end of a function, put ``None`` there yourself.
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.. code-block:: hy
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=> (defn f [x] (setv y 10) (+ x y) None)
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=> (print (f 4))
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None
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set-comp
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--------
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