Merge pull request #898 from algernon/glc/DOWN-WITH-THEM-BRACKETS

A big let and with change

docs/language/api.rst

@@ -213,17 +213,17 @@ Examples of usage:
 
 .. code-block:: clj
 
-  =>(let [[collection {}]]
+  =>(let [collection {}]
   ... (assoc collection "Dog" "Bark")
   ... (print collection))
   {u'Dog': u'Bark'}
 
-  =>(let [[collection {}]]
+  =>(let [collection {}]
   ... (assoc collection "Dog" "Bark" "Cat" "Meow")
   ... (print collection))
   {u'Cat': u'Meow', u'Dog': u'Bark'}
 
-  =>(let [[collection [1 2 3 4]]]
+  =>(let [collection [1 2 3 4]]
   ... (assoc collection 2 None)
   ... (print collection))
   [1, 2, None, 4]
@@ -463,8 +463,8 @@ Parameters may have the following keywords in front of them:
     .. code-block:: clj
 
         => (defn zig-zag-sum [&rest numbers]
-             (let [[odd-numbers (list-comp x [x numbers] (odd? x))]
-	           [even-numbers (list-comp x [x numbers] (even? x))]]
+             (let [odd-numbers (list-comp x [x numbers] (odd? x))
+	           even-numbers (list-comp x [x numbers] (even? x))]
                (- (sum odd-numbers) (sum even-numbers))))
 
         => (zig-zag-sum)
@@ -486,7 +486,7 @@ Parameters may have the following keywords in front of them:
     .. code-block:: clj
 
         => (defn compare [a b &kwonly keyfn [reverse false]]
-        ...  (let [[result (keyfn a b)]]
+        ...  (let [result (keyfn a b)]
         ...    (if (not reverse)
         ...      result
         ...      (- result))))
@@ -786,8 +786,8 @@ list. Example usage:
 
 .. code-block:: clj
 
-   => (let [[animals {"dog" "bark" "cat" "meow"}]
-   ...      [numbers ["zero" "one" "two" "three"]]]
+   => (let [animals {"dog" "bark" "cat" "meow"}
+   ...      numbers ["zero" "one" "two" "three"]]
    ...  (print (get animals "dog"))
    ...  (print (get numbers 2)))
    bark
@@ -988,30 +988,24 @@ example showcases this behaviour:
 
 .. code-block:: clj
 
-    => (let [[x 5]] (print x)
-    ...  (let [[x 6]] (print x))
+    => (let [x 5] (print x)
+    ...  (let [x 6] (print x))
     ...  (print x))
     5
     6
     5
 
-The ``let`` macro takes two parameters: a vector defining *variables* and the
-*body* which gets executed. *variables* is a vector where each element is either
-a single variable or a vector defining a variable value pair. In the case of a
-single variable, it is assigned value ``None``; otherwise, the supplied value is
-used.
-
-.. code-block:: clj
-
-    => (let [x [y 5]] (print x y))
-    None 5
+The ``let`` macro takes two parameters: a vector defining *variables*
+and the *body* which gets executed. *variables* is a vector of
+variable and value pairs.
 
 Note that the variable assignments are executed one by one, from left to right.
 The following example takes advantage of this:
 
 .. code-block:: clj
 
-    => (let [[x 5] [y (+ x 1)]] (print x y))
+    => (let [x 5 
+             y (+ x 1)] (print x y))
     5 6
 
 
@@ -1050,15 +1044,15 @@ to modify variables through nested ``let`` or ``fn`` scopes:
 
 .. code-block:: clj
 
-    (let [[x 0]]
+    (let [x 0]
       (for [y (range 10)]
-        (let [[z (inc y)]]
+        (let [z (inc y)]
           (nonlocal x)  ; allow the setv to "jump scope" to resolve x
           (setv x (+ x y))))
       x)
 
     (defn some-function []
-      (let [[x 0]]
+      (let [x 0]
         (register-some-callback
           (fn [stuff]
             (nonlocal x)
@@ -1369,18 +1363,18 @@ manner. The archetypical example of using ``with`` is when processing files.
 
 .. code-block:: clj
 
-    (with [[arg (expr)]] block)
+    (with [arg (expr)] block)
 
-    (with [[(expr)]] block)
+    (with [(expr)] block)
 
-    (with [[arg (expr)] [(expr)]] block)
+    (with [arg (expr) (expr)] block)
 
 The following example will open the ``NEWS`` file and print its content to the
 screen. The file is automatically closed after it has been processed.
 
 .. code-block:: clj
 
-    (with [[f (open "NEWS")]] (print (.read f)))
+    (with [f (open "NEWS")] (print (.read f)))
 
 
 with-decorator
@@ -1467,9 +1461,9 @@ expands to:
 
 .. code-block:: hy
 
-   (let [[a (gensym)
-         [b (gensym)
-         [c (gensym)]]
+   (let [a (gensym)
+         b (gensym)
+         c (gensym)]
      ...)
 
 .. seealso::

docs/language/core.rst

@@ -1100,10 +1100,10 @@ if *from-file* ends before a complete expression can be parsed.
    => ; assuming "example.hy" contains:
    => ;   (print "hello")
    => ;   (print "hyfriends!")
-   => (with [[f (open "example.hy")]]
+   => (with [f (open "example.hy")]
    ...   (try
    ...     (while true
-   ...            (let [[exp (read f)]]
+   ...            (let [exp (read f)]
    ...              (do
    ...                (print "OHY" exp)
    ...                (eval exp))))

docs/language/internals.rst

@@ -381,7 +381,7 @@ A first pass might be something like:
 .. code-block:: hy
 
    (defmacro nif [expr pos-form zero-form neg-form]
-     `(let [[obscure-name ~expr]]
+     `(let [obscure-name ~expr]
        (cond [(pos? obscure-name) ~pos-form]
              [(zero? obscure-name) ~zero-form]
              [(neg? obscure-name) ~neg-form])))
@@ -396,8 +396,8 @@ such an occasion. A much better version of ``nif`` would be:
 .. code-block:: hy
 
    (defmacro nif [expr pos-form zero-form neg-form]
-     (let [[g (gensym)]]
-       `(let [[~g ~expr]]
+     (let [g (gensym)]
+       `(let [~g ~expr]
           (cond [(pos? ~g) ~pos-form]
                 [(zero? ~g) ~zero-form]
                 [(neg? ~g) ~neg-form]))))
@@ -415,9 +415,9 @@ expands to:
 
 .. code-block:: hy
 
-   (let [[a (gensym)
-         [b (gensym)
-         [c (gensym)]]
+   (let [a (gensym)
+         b (gensym)
+         c (gensym)]
      ...)
 
 so our re-written ``nif`` would look like:
@@ -426,7 +426,7 @@ so our re-written ``nif`` would look like:
 
    (defmacro nif [expr pos-form zero-form neg-form]
      (with-gensyms [g]
-       `(let [[~g ~expr]]
+       `(let [~g ~expr]
           (cond [(pos? ~g) ~pos-form]
                 [(zero? ~g) ~zero-form]
                 [(neg? ~g) ~neg-form]))))
@@ -440,7 +440,7 @@ Our final version of ``nif``, built with ``defmacro/g!`` becomes:
 .. code-block:: hy
 
    (defmacro/g! nif [expr pos-form zero-form neg-form]
-     `(let [[~g!res ~expr]]
+     `(let [~g!res ~expr]
         (cond [(pos? ~g!res) ~pos-form]
               [(zero? ~g!res) ~zero-form]
               [(neg? ~g!res) ~neg-form]))))

docs/style-guide.rst

@@ -105,8 +105,8 @@ Layout & Indentation
 
   .. code-block:: clj
 
-     (let [[foo (bar)]
-           [qux (baz)]]
+     (let [foo (bar)]
+           qux (baz)]
         (foo qux))
 
 

docs/tutorial.rst

@@ -335,7 +335,7 @@ Python's context managers (``with`` statements) are used like this:
 
 .. code-block:: clj
 
-     (with [[f (open "/tmp/data.in")]]
+     (with [f (open "/tmp/data.in")]
        (print (.read f)))
 
 which is equivalent to::

eg/twisted/get-page.hy

@@ -27,7 +27,7 @@
   (reactor.stop))
 
 (defn get-page [url]
-  (let [[d (getPage url)]]
+  (let [d (getPage url)]
     (d.addCallback get-page-size)
     (d.addErrback log-error)
     (d.addCallback finish)))

hy/contrib/alias.hy

@@ -30,8 +30,8 @@
 
 (defmacro defn-alias [names lambda-list &rest body]
   "define one function with several names"
-  (let [[main (first names)]
-        [aliases (rest names)]]
+  (let [main (first names)
+        aliases (rest names)]
     (setv ret `(do (defn ~main ~lambda-list ~@body)))
     (for* [name aliases]
       (.append ret

hy/contrib/anaphoric.hy

@@ -26,7 +26,7 @@
 
 
 (defmacro ap-if (test-form &rest args)
-  `(let [[it ~test-form]] (if it ~@args)))
+  `(let [it ~test-form] (if it ~@args)))
 
 
 (defmacro ap-each [lst &rest body]
@@ -37,7 +37,7 @@
 (defmacro ap-each-while [lst form &rest body]
   "Evalutate the body form for each element in the list while the
   predicate form evaluates to True."
-  `(let [[p (lambda [it] ~form)]]
+  `(let [p (lambda [it] ~form)]
      (for [it ~lst]
        (if (p it)
          ~@body
@@ -46,16 +46,17 @@
 
 (defmacro ap-map [form lst]
   "Yield elements evaluated in the form for each element in the list."
-  (let [[v (gensym 'v)] [f (gensym 'f)]]
-    `(let [[~f (lambda [it] ~form)]]
+  (let [v (gensym 'v)
+        f (gensym 'f)]
+    `(let [~f (lambda [it] ~form)]
        (for [~v ~lst]
          (yield (~f ~v))))))
 
 
 (defmacro ap-map-when [predfn rep lst]
   "Yield elements evaluated for each element in the list when the
   predicate function returns True."
-  `(let [[f (lambda [it] ~rep)]]
+  `(let [f (lambda [it] ~rep)]
      (for [it ~lst]
        (if (~predfn it)
          (yield (f it))
@@ -64,7 +65,7 @@
 
 (defmacro ap-filter [form lst]
   "Yield elements returned when the predicate form evaluates to True."
-  `(let [[pred (lambda [it] ~form)]]
+  `(let [pred (lambda [it] ~form)]
      (for [val ~lst]
        (if (pred val)
          (yield val)))))
@@ -85,15 +86,15 @@
 (defmacro ap-first [predfn lst]
   "Yield the first element that passes `predfn`"
   (with-gensyms [n]
-    `(let [[~n None]]
+    `(let [~n None]
        (ap-each ~lst (when ~predfn (setv ~n it) (break)))
        ~n)))
 
 
 (defmacro ap-last [predfn lst]
   "Yield the last element that passes `predfn`"
   (with-gensyms [n]
-    `(let [[~n None]]
+    `(let [~n None]
        (ap-each ~lst (none? ~n)
                 (when ~predfn
                   (setv ~n it)))
@@ -103,10 +104,10 @@
 (defmacro ap-reduce [form lst &optional [initial-value None]]
   "Anaphoric form of reduce, `acc' and `it' can be used for a form"
   (if (none? initial-value)
-    `(let [[acc (car ~lst)]]
+    `(let [acc (car ~lst)]
        (ap-each (cdr ~lst) (setv acc ~form))
        acc)
-    `(let [[acc ~initial-value]]
+    `(let [acc ~initial-value]
        (ap-each ~lst (setv acc ~form))
        acc)))
 
@@ -115,7 +116,7 @@
   "Pushes a value through several forms.
   (Anaphoric version of -> and ->>)"
   (if (empty? forms) var
-      `(ap-pipe (let [[it ~var]] ~(first forms)) ~@(rest forms))))
+      `(ap-pipe (let [it ~var] ~(first forms)) ~@(rest forms))))
 
 
 (defmacro ap-compose [&rest forms]

hy/contrib/botsbuildbots.hy

@@ -26,8 +26,8 @@
     (do
      (import [requests])
 
-     (let [[r (requests.get
-               "https://raw.githubusercontent.com/hylang/hy/master/AUTHORS")]]
+     (let [r (requests.get
+              "https://raw.githubusercontent.com/hylang/hy/master/AUTHORS")]
        (repeat r.text)))
     (except [e ImportError]
       (repeat "Botsbuildbots requires `requests' to function."))))

hy/contrib/curry.hy

@@ -2,8 +2,8 @@
 
 
 (defn curry [func]
-  (let [[sig (.getargspec inspect func)]
-        [count (len sig.args)]]
+  (let [sig (.getargspec inspect func)
+        count (len sig.args)]
 
     (fn [&rest args]
       (if (< (len args) count)

hy/contrib/loop.hy

@@ -58,7 +58,7 @@
 
 
 (defmacro/g! fnr [signature &rest body]
-  (let [[new-body (recursive-replace 'recur g!recur-fn body)]]
+  (let [new-body (recursive-replace 'recur g!recur-fn body)]
     `(do
       (import [hy.contrib.loop [--trampoline--]])
       (with-decorator
@@ -85,7 +85,7 @@
   ;; If recur is used in a non-tail-call position, None is returned, which
   ;; causes chaos. Fixing this to detect if recur is in a tail-call position
   ;; and erroring if not is a giant TODO.
-  (let [[fnargs (map (fn [x] (first x)) bindings)]
-        [initargs (map second bindings)]]
+  (let [fnargs (map (fn [x] (first x)) bindings)
+        initargs (map second bindings)]
     `(do (defnr ~g!recur-fn [~@fnargs] ~@body)
          (~g!recur-fn ~@initargs))))

hy/contrib/meth.hy

@@ -3,11 +3,11 @@
 
 (defmacro route-with-methods [name path methods params &rest code]
   "Same as route but with an extra methods array to specify HTTP methods"
-  `(let [[deco (apply app.route [~path]
-                                    {"methods" ~methods})]]
-                 (with-decorator deco
-                   (defn ~name ~params 
-                     (do ~@code)))))
+  `(let [deco (apply app.route [~path]
+                     {"methods" ~methods})]
+     (with-decorator deco
+       (defn ~name ~params
+         (do ~@code)))))
 
 ;; Some macro examples
 (defmacro route [name path params &rest code]