De-bracing | part 2

42 files changed, 253 insertions, 227 deletions

diff --git a/stdlib/source/library/lux.lux b/stdlib/source/library/lux.lux
index d10f8d2f5..0872e57c1 100644
--- a/stdlib/source/library/lux.lux
+++ b/stdlib/source/library/lux.lux
@@ -4868,15 +4868,34 @@
         (in_meta (list pick))
         (target_pick target options' default)))))
 
+(def: (pairs' tokens)
+  (-> (List Code) (Maybe (List [Code Code])))
+  (if (|> tokens
+          list\size
+          (n/% 2)
+          ("lux i64 =" 0))
+    (#Some (pairs tokens))
+    #None))
+
 (macro: .public (for tokens)
   (do meta_monad
     [target ..target]
     (case tokens
-      (^ (list [_ (#Record options)]))
-      (target_pick target options #None)
+      (^ (list [_ (#Tuple options)]))
+      (case (pairs' options)
+        (#Some options)
+        (target_pick target options #None)
+
+        #None
+        (failure (..wrong_syntax_error (name_of ..for))))
       
-      (^ (list [_ (#Record options)] default))
-      (target_pick target options (#Some default))
+      (^ (list [_ (#Tuple options)] default))
+      (case (pairs' options)
+        (#Some options)
+        (target_pick target options (#Some default))
+
+        #None
+        (failure (..wrong_syntax_error (name_of ..for))))
 
       _
       (failure (..wrong_syntax_error (name_of ..for))))))
diff --git a/stdlib/source/library/lux/abstract/apply.lux b/stdlib/source/library/lux/abstract/apply.lux
index 48598dfa5..f1b2b9344 100644
--- a/stdlib/source/library/lux/abstract/apply.lux
+++ b/stdlib/source/library/lux/abstract/apply.lux
@@ -26,10 +26,10 @@
   
   (def: (on fgx fgf)
     ... TODO: Switch from this version to the one below (in comments) ASAP.
-    (for {@.old (let [fgf' (\ f_apply on
+    (for [@.old (let [fgf' (\ f_apply on
                               fgf
                               (\ f_monad in (function (_ gf gx) (\ g_apply on gx gf))))]
-                  (:expected (\ f_apply on (:expected fgx) (:expected fgf'))))}
+                  (:expected (\ f_apply on (:expected fgx) (:expected fgf'))))]
          (let [fgf' (\ f_apply on
                        fgf
                        (\ f_monad in (function (_ gf gx) (\ g_apply on gx gf))))]
diff --git a/stdlib/source/library/lux/control/concatenative.lux b/stdlib/source/library/lux/control/concatenative.lux
index 24883f901..28a48035f 100644
--- a/stdlib/source/library/lux/control/concatenative.lux
+++ b/stdlib/source/library/lux/control/concatenative.lux
@@ -38,8 +38,7 @@
   (Parser (List Alias))
   (|> (<>.and <code>.local_identifier <code>.any)
       <>.some
-      <code>.record
-      (<>.else (list))))
+      <code>.tuple))
 
 (def: top^
   (Parser (List Code))
@@ -75,9 +74,12 @@
       (meta.failure (format "Cannot expand to more than a single AST/Code node:" text.new_line
                             (|> expansion (list\each %.code) (text.interposed " ")))))))
 
-(syntax: .public (=> [aliases aliases^
-                      inputs stack^
-                      outputs stack^])
+(def: signature^
+  (Parser [(List Alias) Stack Stack])
+  (<>.either ($_ <>.and aliases^ stack^ stack^)
+             ($_ <>.and (<>\in (list)) stack^ stack^)))
+
+(syntax: .public (=> [[aliases inputs outputs] signature^])
   (let [de_alias (function (_ aliased)
                    (list\mix (function (_ [from to] pre)
                                (code.replaced (code.local_identifier from) to pre))
@@ -248,26 +250,26 @@
   )
 
 (def: .public if
-  (All (_ ___a ___z)
-    (=> {then (=> ___a ___z)
-         else (=> ___a ___z)}
-        ___a [Bit then else] ___z))
+  (All (_ ,,,0 ,,,1)
+    (=> [then (=> ,,,0 ,,,1)
+         else (=> ,,,0 ,,,1)]
+        ,,,0 [Bit then else] ,,,1))
   (function (_ [[[stack test] then] else])
     (.if test
       (then stack)
       (else stack))))
 
 (def: .public call
-  (All (_ ___a ___z)
-    (=> {quote (=> ___a ___z)}
-        ___a [quote] ___z))
+  (All (_ ,,,0 ,,,1)
+    (=> [quote (=> ,,,0 ,,,1)]
+        ,,,0 [quote] ,,,1))
   (function (_ [stack quote])
     (quote stack)))
 
 (def: .public loop
-  (All (_ ___)
-    (=> {test (=> ___ ___ [Bit])}
-        ___ [test] ___))
+  (All (_ ,,,)
+    (=> [test (=> ,,, ,,, [Bit])]
+        ,,, [test] ,,,))
   (function (loop [stack pred])
     (let [[stack' verdict] (pred stack)]
       (.if verdict
@@ -275,34 +277,34 @@
         stack'))))
 
 (def: .public dip
-  (All (_ ___ a)
-    (=> ___ [a (=> ___ ___)]
-        ___ [a]))
+  (All (_ ,,, a)
+    (=> ,,, [a (=> ,,, ,,,)]
+        ,,, [a]))
   (function (_ [[stack a] quote])
     [(quote stack) a]))
 
 (def: .public dip/2
-  (All (_ ___ a b)
-    (=> ___ [a b (=> ___ ___)]
-        ___ [a b]))
+  (All (_ ,,, a b)
+    (=> ,,, [a b (=> ,,, ,,,)]
+        ,,, [a b]))
   (function (_ [[[stack a] b] quote])
     [[(quote stack) a] b]))
 
 (def: .public do
-  (All (_ ___a ___z)
-    (=> {body (=> ___a ___z)
-         pred (=> ___z ___a [Bit])}
-        ___a [pred body]
-        ___z [pred body]))
+  (All (_ ,,,0 ,,,1)
+    (=> [body (=> ,,,0 ,,,1)
+         pred (=> ,,,1 ,,,0 [Bit])]
+        ,,,0 [pred body]
+        ,,,1 [pred body]))
   (function (_ [[stack pred] body])
     [[(body stack) pred] body]))
 
 (def: .public while
-  (All (_ ___a ___z)
-    (=> {body (=> ___z ___a)
-         pred (=> ___a ___z [Bit])}
-        ___a [pred body]
-        ___z))
+  (All (_ ,,,0 ,,,1)
+    (=> [body (=> ,,,1 ,,,0)
+         pred (=> ,,,0 ,,,1 [Bit])]
+        ,,,0 [pred body]
+        ,,,1))
   (function (while [[stack pred] body])
     (let [[stack' verdict] (pred stack)]
       (.if verdict
@@ -310,24 +312,24 @@
         stack'))))
 
 (def: .public compose
-  (All (_ ___a ___ ___z)
-    (=> [(=> ___a ___) (=> ___ ___z)]
-        [(=> ___a ___z)]))
+  (All (_ ,,,0 ,,, ,,,1)
+    (=> [(=> ,,,0 ,,,) (=> ,,, ,,,1)]
+        [(=> ,,,0 ,,,1)]))
   (function (_ [[stack f] g])
     [stack (|>> f g)]))
 
 (def: .public partial
-  (All (_ ___a ___z a)
-    (=> ___a [a (=> ___a [a] ___z)]
-        ___a [(=> ___a ___z)]))
+  (All (_ ,,,0 ,,,1 a)
+    (=> ,,,0 [a (=> ,,,0 [a] ,,,1)]
+        ,,,0 [(=> ,,,0 ,,,1)]))
   (function (_ [[stack arg] quote])
     [stack (|>> (push arg) quote)]))
 
 (word: .public when
-  (All (_ ___)
-    (=> {body (=> ___ ___)}
-        ___ [Bit body]
-        ___))
+  (All (_ ,,,)
+    (=> [body (=> ,,, ,,,)]
+        ,,, [Bit body]
+        ,,,))
   swap
   (push ..call)
   (push ..drop)
diff --git a/stdlib/source/library/lux/control/concurrency/atom.lux b/stdlib/source/library/lux/control/concurrency/atom.lux
index 6309f4f35..091273281 100644
--- a/stdlib/source/library/lux/control/concurrency/atom.lux
+++ b/stdlib/source/library/lux/control/concurrency/atom.lux
@@ -20,57 +20,57 @@
                                   (new [a])
                                   (get [] a)
                                   (compareAndSet [a a] boolean)]))]
-  (for {@.old <jvm>
-        @.jvm <jvm>}
+  (for [@.old <jvm>
+        @.jvm <jvm>]
        (as_is)))
 
-(with_expansions [<new> (for {@.js "js array new"
+(with_expansions [<new> (for [@.js "js array new"
                               @.python "python array new"
                               @.lua "lua array new"
                               @.ruby "ruby array new"
                               @.php "php array new"
-                              @.scheme "scheme array new"}
+                              @.scheme "scheme array new"]
                              (as_is))
-                  <write> (for {@.js "js array write"
+                  <write> (for [@.js "js array write"
                                 @.python "python array write"
                                 @.lua "lua array write"
                                 @.ruby "ruby array write"
                                 @.php "php array write"
-                                @.scheme "scheme array write"}
+                                @.scheme "scheme array write"]
                                (as_is))
                   
-                  <read> (for {@.js "js array read"
+                  <read> (for [@.js "js array read"
                                @.python "python array read"
                                @.lua "lua array read"
                                @.ruby "ruby array read"
                                @.php "php array read"
-                               @.scheme "scheme array read"}
+                               @.scheme "scheme array read"]
                               (as_is))]
   (abstract: .public (Atom a)
     (with_expansions [<jvm> (java/util/concurrent/atomic/AtomicReference a)]
-      (for {@.old <jvm>
-            @.jvm <jvm>}
+      (for [@.old <jvm>
+            @.jvm <jvm>]
            (array.Array a)))
 
     [(def: .public (atom value)
        (All (_ a) (-> a (Atom a)))
        (:abstraction (with_expansions [<jvm> (java/util/concurrent/atomic/AtomicReference::new value)]
-                       (for {@.old <jvm>
-                             @.jvm <jvm>}
+                       (for [@.old <jvm>
+                             @.jvm <jvm>]
                             (<write> 0 value (<new> 1))))))
 
      (def: .public (read! atom)
        (All (_ a) (-> (Atom a) (IO a)))
        (io.io (with_expansions [<jvm> (java/util/concurrent/atomic/AtomicReference::get (:representation atom))]
-                (for {@.old <jvm>
-                      @.jvm <jvm>}
+                (for [@.old <jvm>
+                      @.jvm <jvm>]
                      (<read> 0 (:representation atom))))))
 
      (def: .public (compare_and_swap! current new atom)
        (All (_ a) (-> a a (Atom a) (IO Bit)))
        (io.io (with_expansions [<jvm> (java/util/concurrent/atomic/AtomicReference::compareAndSet current new (:representation atom))]
-                (for {@.old <jvm>
-                      @.jvm <jvm>}
+                (for [@.old <jvm>
+                      @.jvm <jvm>]
                      (let [old (<read> 0 (:representation atom))]
                        (if (same? old current)
                          (exec (<write> 0 new (:representation atom))
diff --git a/stdlib/source/library/lux/control/concurrency/thread.lux b/stdlib/source/library/lux/control/concurrency/thread.lux
index 4e82d76a6..c9430c1ed 100644
--- a/stdlib/source/library/lux/control/concurrency/thread.lux
+++ b/stdlib/source/library/lux/control/concurrency/thread.lux
@@ -45,7 +45,7 @@
                                  ["[1]::[0]"
                                   (new [int])
                                   (schedule [java/lang/Runnable long java/util/concurrent/TimeUnit] "io" (java/util/concurrent/ScheduledFuture java/lang/Object))]))]
-  (for {@.old (as_is <jvm>)
+  (for [@.old (as_is <jvm>)
         @.jvm (as_is <jvm>)
 
         @.js
@@ -55,7 +55,7 @@
         (ffi.import: threading/Timer
           ["[1]::[0]"
            (new [ffi.Float ffi.Function])
-           (start [] "io" "?" Any)])}
+           (start [] "io" "?" Any)])]
        
        ... Default
        (type: Thread
@@ -70,18 +70,18 @@
   (with_expansions [<jvm> (|> (java/lang/Runtime::getRuntime)
                               (java/lang/Runtime::availableProcessors)
                               .nat)]
-    (for {@.old <jvm>
-          @.jvm <jvm>}
+    (for [@.old <jvm>
+          @.jvm <jvm>]
          ... Default
          1)))
 
 (with_expansions [<jvm> (as_is (def: runner
                                  java/util/concurrent/ScheduledThreadPoolExecutor
                                  (java/util/concurrent/ScheduledThreadPoolExecutor::new (.int ..parallelism))))]
-  (for {@.old <jvm>
+  (for [@.old <jvm>
         @.jvm <jvm>
         @.js (as_is)
-        @.python (as_is)}
+        @.python (as_is)]
        
        ... Default
        (def: runner
@@ -111,7 +111,7 @@
                                      0 (java/util/concurrent/Executor::execute runnable runner)
                                      _ (java/util/concurrent/ScheduledThreadPoolExecutor::schedule runnable (.int milli_seconds) java/util/concurrent/TimeUnit::MILLISECONDS
                                                                                                    runner))))]
-    (for {@.old <jvm>
+    (for [@.old <jvm>
           @.jvm <jvm>
 
           @.js
@@ -124,7 +124,7 @@
                    [(|> milli_seconds n.frac (f./ +1,000.0))]
                    threading/Timer::new
                    (threading/Timer::start []))]
-            (in []))}
+            (in []))]
          
          ... Default
          (do [! io.monad]
@@ -135,10 +135,10 @@
                             ..runner)]
            (in [])))))
 
-(for {@.old (as_is)
+(for [@.old (as_is)
       @.jvm (as_is)
       @.js (as_is)
-      @.python (as_is)}
+      @.python (as_is)]
      
      ... Default
      (as_is (exception: .public cannot_continue_running_threads)
diff --git a/stdlib/source/library/lux/control/thread.lux b/stdlib/source/library/lux/control/thread.lux
index b2945a7a0..ec49d9a1a 100644
--- a/stdlib/source/library/lux/control/thread.lux
+++ b/stdlib/source/library/lux/control/thread.lux
@@ -30,7 +30,7 @@
    (def: .public (read! box)
      (All (_ ! a) (-> (Box ! a) (Thread ! a)))
      (function (_ !)
-       (for {@.old
+       (for [@.old
              ("jvm aaload" (:representation box) 0)
 
              @.jvm
@@ -46,7 +46,7 @@
              @.lua ("lua array read" 0 (:representation box))
              @.ruby ("ruby array read" 0 (:representation box))
              @.php ("php array read" 0 (:representation box))
-             @.scheme ("scheme array read" 0 (:representation box))})))
+             @.scheme ("scheme array read" 0 (:representation box))])))
 
    (def: .public (write! value box)
      (All (_ a) (-> a (All (_ !) (-> (Box ! a) (Thread ! Any)))))
diff --git a/stdlib/source/library/lux/control/writer.lux b/stdlib/source/library/lux/control/writer.lux
index cabc9268c..0805da036 100644
--- a/stdlib/source/library/lux/control/writer.lux
+++ b/stdlib/source/library/lux/control/writer.lux
@@ -62,9 +62,9 @@
   
   (def: (conjoint MlMla)
     (do monad
-      [[l1 Mla] (for {@.old
+      [[l1 Mla] (for [@.old
                       (: ((:parameter 1) (Writer (:parameter 0) ((:parameter 1) (Writer (:parameter 0) (:parameter 2)))))
-                         MlMla)}
+                         MlMla)]
                      ... On new compiler
                      MlMla)
        [l2 a] Mla]
diff --git a/stdlib/source/library/lux/data/binary.lux b/stdlib/source/library/lux/data/binary.lux
index 8d1975b8f..33bac997b 100644
--- a/stdlib/source/library/lux/data/binary.lux
+++ b/stdlib/source/library/lux/data/binary.lux
@@ -60,12 +60,12 @@
 
                                (def: byte
                                  (-> (I64 Any) (primitive "java.lang.Byte"))
-                                 (for {@.old
+                                 (for [@.old
                                        (|>> .int ffi.long_to_byte)
 
                                        @.jvm
-                                       (|>> .int (:as (primitive "java.lang.Long")) ffi.long_to_byte)})))]
-  (for {@.old (as_is <jvm>)
+                                       (|>> .int (:as (primitive "java.lang.Long")) ffi.long_to_byte)])))]
+  (for [@.old (as_is <jvm>)
         @.jvm (as_is <jvm>)
 
         @.js
@@ -92,14 +92,14 @@
                (ffi.import: (make-bytevector [Nat] Binary))
                (ffi.import: (bytevector-u8-ref [Binary Nat] I64))
                (ffi.import: (bytevector-u8-set! [Binary Nat (I64 Any)] Any))
-               (ffi.import: (bytevector-length [Binary] Nat)))}
+               (ffi.import: (bytevector-length [Binary] Nat)))]
 
        ... Default
        (type: .public Binary
          (array.Array (I64 Any)))))
 
 (template: (!size binary)
-  [(for {@.old (ffi.length binary)
+  [(for [@.old (ffi.length binary)
          @.jvm (ffi.length binary)
 
          @.js
@@ -113,13 +113,13 @@
              "python array length")
 
          @.scheme
-         (..bytevector-length [binary])}
+         (..bytevector-length [binary])]
 
         ... Default
         (array.size binary))])
 
 (template: (!read index binary)
-  [(for {@.old (..i64 (ffi.read! index binary))
+  [(for [@.old (..i64 (ffi.read! index binary))
          @.jvm (..i64 (ffi.read! index binary))
 
          @.js
@@ -136,7 +136,7 @@
              ("python array read" index))
 
          @.scheme
-         (..bytevector-u8-ref [binary index])}
+         (..bytevector-u8-ref [binary index])]
 
         ... Default
         (|> binary
@@ -152,13 +152,13 @@
        (:as ..Binary))])
 
 (template: (!write index value binary)
-  [(for {@.old (ffi.write! index (..byte value) binary)
+  [(for [@.old (ffi.write! index (..byte value) binary)
          @.jvm (ffi.write! index (..byte value) binary)
 
          @.js (!!write .Frac n.frac "js array write" index value binary)
          @.python (!!write (I64 Any) (:as (I64 Any)) "python array write" index value binary)
          @.scheme (exec (..bytevector-u8-set! [binary index value])
-                    binary)}
+                    binary)]
 
         ... Default
         (array.write! index (|> value .nat (n.% (hex "100"))) binary))])
@@ -169,7 +169,7 @@
 
 (def: .public (empty size)
   (-> Nat Binary)
-  (for {@.old (ffi.array byte size)
+  (for [@.old (ffi.array byte size)
         @.jvm (ffi.array byte size)
 
         @.js
@@ -181,7 +181,7 @@
             (:as Binary))
 
         @.scheme
-        (..make-bytevector size)}
+        (..make-bytevector size)]
 
        ... Default
        (array.empty size)))
@@ -261,7 +261,7 @@
 (def: .public (write/64! index value binary)
   (-> Nat (I64 Any) Binary (Try Binary))
   (if (n.< (..!size binary) (n.+ 7 index))
-    (for {@.scheme (let [write_high (|>> (!write index (i64.right_shifted 56 value))
+    (for [@.scheme (let [write_high (|>> (!write index (i64.right_shifted 56 value))
                                          (!write (n.+ 1 index) (i64.right_shifted 48 value))
                                          (!write (n.+ 2 index) (i64.right_shifted 40 value))
                                          (!write (n.+ 3 index) (i64.right_shifted 32 value)))
@@ -269,7 +269,7 @@
                                         (!write (n.+ 5 index) (i64.right_shifted 16 value))
                                         (!write (n.+ 6 index) (i64.right_shifted 8 value))
                                         (!write (n.+ 7 index) value))]
-                     (|> binary write_high write_low #try.Success))}
+                     (|> binary write_high write_low #try.Success))]
          (#try.Success (|> binary
                            (!write index (i64.right_shifted 56 value))
                            (!write (n.+ 1 index) (i64.right_shifted 48 value))
@@ -286,8 +286,8 @@
   
   (def: (= reference sample)
     (with_expansions [<jvm> (java/util/Arrays::equals reference sample)]
-      (for {@.old <jvm>
-            @.jvm <jvm>}
+      (for [@.old <jvm>
+            @.jvm <jvm>]
            (let [limit (!size reference)]
              (and (n.= limit
                        (!size sample))
@@ -298,8 +298,8 @@
                            (recur (++ index)))
                       true))))))))
 
-(for {@.old (as_is)
-      @.jvm (as_is)}
+(for [@.old (as_is)
+      @.jvm (as_is)]
 
      ... Default
      (exception: .public (cannot_copy_bytes [bytes Nat
@@ -315,8 +315,8 @@
   (with_expansions [<jvm> (as_is (do try.monad
                                    [_ (java/lang/System::arraycopy source (.int source_offset) target (.int target_offset) (.int bytes))]
                                    (in target)))]
-    (for {@.old <jvm>
-          @.jvm <jvm>}
+    (for [@.old <jvm>
+          @.jvm <jvm>]
          
          ... Default
          (let [source_input (n.- source_offset (!size source))
@@ -338,8 +338,8 @@
     (if (n.> size limit)
       (exception.except ..slice_out_of_bounds [size offset length])
       (with_expansions [<jvm> (as_is (#try.Success (java/util/Arrays::copyOfRange binary (.int offset) (.int limit))))]
-        (for {@.old <jvm>
-              @.jvm <jvm>}
+        (for [@.old <jvm>
+              @.jvm <jvm>]
              
              ... Default
              (..copy length offset binary 0 (..empty length)))))))
diff --git a/stdlib/source/library/lux/data/collection/array.lux b/stdlib/source/library/lux/data/collection/array.lux
index 3c04a7d7f..0bd99245d 100644
--- a/stdlib/source/library/lux/data/collection/array.lux
+++ b/stdlib/source/library/lux/data/collection/array.lux
@@ -27,17 +27,17 @@
 (with_expansions [<index_type> (primitive "java.lang.Long")
                   <elem_type> (primitive "java.lang.Object")
                   <array_type> (type (Array <elem_type>))]
-  (for {@.jvm
+  (for [@.jvm
         (template: (!int value)
           [(|> value
                (:as <index_type>)
                "jvm object cast"
-               "jvm conversion long-to-int")])}
+               "jvm conversion long-to-int")])]
        (as_is))
   
   (def: .public (empty size)
     (All (_ a) (-> Nat (Array a)))
-    (for {@.old
+    (for [@.old
           (:expected ("jvm anewarray" "(java.lang.Object )" size))
 
           @.jvm
@@ -52,11 +52,11 @@
           @.lua ("lua array new" size)
           @.ruby ("ruby array new" size)
           @.php ("php array new" size)
-          @.scheme ("scheme array new" size)}))
+          @.scheme ("scheme array new" size)]))
 
   (def: .public (size array)
     (All (_ a) (-> (Array a) Nat))
-    (for {@.old
+    (for [@.old
           ("jvm arraylength" array)
 
           @.jvm
@@ -73,7 +73,7 @@
           @.lua ("lua array length" array)
           @.ruby ("ruby array length" array)
           @.php ("php array length" array)
-          @.scheme ("scheme array length" array)}))
+          @.scheme ("scheme array length" array)]))
 
   (template: (!read! <read!> <null?>)
     [(let [output (<read!> index array)]
@@ -85,7 +85,7 @@
     (All (_ a)
       (-> Nat (Array a) (Maybe a)))
     (if (n.< (size array) index)
-      (for {@.old
+      (for [@.old
             (let [value ("jvm aaload" array index)]
               (if ("jvm object null?" value)
                 #.None
@@ -104,13 +104,13 @@
             @.lua (!read! "lua array read" "lua object nil?")
             @.ruby (!read! "ruby array read" "ruby object nil?")
             @.php (!read! "php array read" "php object null?")
-            @.scheme (!read! "scheme array read" "scheme object nil?")})
+            @.scheme (!read! "scheme array read" "scheme object nil?")])
       #.None))
 
   (def: .public (write! index value array)
     (All (_ a)
       (-> Nat a (Array a) (Array a)))
-    (for {@.old
+    (for [@.old
           ("jvm aastore" array index value)
 
           @.jvm
@@ -124,13 +124,13 @@
           @.lua ("lua array write" index value array)
           @.ruby ("ruby array write" index value array)
           @.php ("php array write" index value array)
-          @.scheme ("scheme array write" index value array)}))
+          @.scheme ("scheme array write" index value array)]))
 
   (def: .public (delete! index array)
     (All (_ a)
       (-> Nat (Array a) (Array a)))
     (if (n.< (size array) index)
-      (for {@.old
+      (for [@.old
             (write! index (:expected ("jvm object null")) array)
 
             @.jvm
@@ -141,7 +141,7 @@
             @.lua ("lua array delete" index array)
             @.ruby ("ruby array delete" index array)
             @.php ("php array delete" index array)
-            @.scheme ("scheme array delete" index array)})
+            @.scheme ("scheme array delete" index array)])
       array))
   )
 
diff --git a/stdlib/source/library/lux/data/collection/list.lux b/stdlib/source/library/lux/data/collection/list.lux
index ead69db05..286290c96 100644
--- a/stdlib/source/library/lux/data/collection/list.lux
+++ b/stdlib/source/library/lux/data/collection/list.lux
@@ -203,7 +203,7 @@
 (def: .public (all check xs)
   (All (_ a b)
     (-> (-> a (Maybe b)) (List a) (List b)))
-  (for {... TODO: Stop relying on this ASAP.
+  (for [... TODO: Stop relying on this ASAP.
         @.js
         (mix (function (_ head tail)
                (case (check head)
@@ -213,7 +213,7 @@
                  #.None
                  tail))
              #.End
-             (reversed xs))}
+             (reversed xs))]
        (case xs
          #.End
          #.End
@@ -572,9 +572,9 @@
     (do [! monad]
       [lMla MlMla
        ... TODO: Remove this version ASAP and use one below.
-       lla (for {@.old
+       lla (for [@.old
                  (: ((:parameter 0) (List (List (:parameter 1))))
-                    (monad.all ! lMla))}
+                    (monad.all ! lMla))]
                 (monad.all ! lMla))]
       (in (..together lla)))))
 
diff --git a/stdlib/source/library/lux/data/collection/row.lux b/stdlib/source/library/lux/data/collection/row.lux
index 5080c4c1c..728a67ce4 100644
--- a/stdlib/source/library/lux/data/collection/row.lux
+++ b/stdlib/source/library/lux/data/collection/row.lux
@@ -224,9 +224,9 @@
             ... If so, a brand-new root must be established, that is
             ... 1-level taller.
             (|> row
-                (with@ #root (|> (for {@.old
+                (with@ #root (|> (for [@.old
                                        (: (Hierarchy (:parameter 0))
-                                          (empty_hierarchy []))}
+                                          (empty_hierarchy []))]
                                       (empty_hierarchy []))
                                  (array.write! 0 (#Hierarchy (value@ #root row)))
                                  (array.write! 1 (..path (value@ #level row) (value@ #tail row)))))
@@ -293,9 +293,9 @@
       (#try.Success (if (n.< (tail_off row_size) idx)
                       (revised@ #root (hierarchy\has (value@ #level row) idx val)
                                 row)
-                      (revised@ #tail (for {@.old
+                      (revised@ #tail (for [@.old
                                             (: (-> (Base (:parameter 0)) (Base (:parameter 0)))
-                                               (|>> array.clone (array.write! (branch_idx idx) val)))}
+                                               (|>> array.clone (array.write! (branch_idx idx) val)))]
                                            (|>> array.clone (array.write! (branch_idx idx) val)))
                                 row)))
       (exception.except ..index_out_of_bounds [row idx]))))
diff --git a/stdlib/source/library/lux/data/collection/tree/zipper.lux b/stdlib/source/library/lux/data/collection/tree/zipper.lux
index 36b162843..ee7daa341 100644
--- a/stdlib/source/library/lux/data/collection/tree/zipper.lux
+++ b/stdlib/source/library/lux/data/collection/tree/zipper.lux
@@ -103,13 +103,13 @@
   (do maybe.monad
     [family (value@ #family zipper)]
     (in (let [(^slots [#parent #lefts #rights]) family]
-          (for {@.old
+          (for [@.old
                 (revised@ #node (: (-> (Tree (:parameter 0))
                                        (Tree (:parameter 0)))
                                    (with@ #//.children (list\composite (list.reversed lefts)
                                                                        (#.Item (value@ #node zipper)
                                                                                rights))))
-                          parent)}
+                          parent)]
                (with@ [#node #//.children]
                       (list\composite (list.reversed lefts)
                                       (#.Item (value@ #node zipper)
@@ -123,11 +123,11 @@
        (#.Some family)
        (case (value@ <side> family)
          (#.Item next side')
-         (#.Some (for {@.old
+         (#.Some (for [@.old
                        [#family (#.Some (|> family
                                             (with@ <side> side')
                                             (revised@ <op_side> (|>> (#.Item (value@ #node zipper))))))
-                        #node next]}
+                        #node next]]
                       (let [move (: (All (_ a) (-> (List (Tree a)) (Zipper a) (Family Zipper a) (Family Zipper a)))
                                     (function (_ side' zipper)
                                       (|>> (with@ <side> side')
@@ -153,11 +153,11 @@
          #.None
 
          (#.Item last prevs)
-         (#.Some (for {@.old [#family (#.Some (|> family
+         (#.Some (for [@.old [#family (#.Some (|> family
                                                   (with@ <side> #.End)
                                                   (revised@ <op_side> (|>> (#.Item (value@ #node zipper))
                                                                            (list\composite prevs)))))
-                              #node last]}
+                              #node last]]
                       (let [move (: (All (_ a) (-> (List (Tree a)) (Zipper a) (Family Zipper a) (Family Zipper a)))
                                     (function (_ prevs zipper)
                                       (|>> (with@ <side> #.End)
diff --git a/stdlib/source/library/lux/data/text.lux b/stdlib/source/library/lux/data/text.lux
index aadcb9dbe..b3961edc4 100644
--- a/stdlib/source/library/lux/data/text.lux
+++ b/stdlib/source/library/lux/data/text.lux
@@ -184,7 +184,7 @@
 
 (def: .public (replaced pattern replacement template)
   (-> Text Text Text Text)
-  (for {@.old
+  (for [@.old
         (:as Text
              ("jvm invokevirtual:java.lang.String:replace:java.lang.CharSequence,java.lang.CharSequence"
               (:as (primitive "java.lang.String") template)
@@ -214,7 +214,7 @@
         ... TODO @.scheme
         ... TODO @.common_lisp
         ... TODO @.r
-        }
+        ]
        ... Inefficient default
        (loop [left ""
               right template]
@@ -253,7 +253,7 @@
   (def: &equivalence ..equivalence)
   
   (def: (hash input)
-    (for {@.old
+    (for [@.old
           (|> input
               (: (primitive "java.lang.String"))
               "jvm invokevirtual:java.lang.String:hashCode:"
@@ -267,7 +267,7 @@
               "jvm conversion int-to-long"
               "jvm object cast"
               (: (primitive "java.lang.Long"))
-              (:as Nat))}
+              (:as Nat))]
          ... Platform-independent default.
          (let [length ("lux text size" input)]
            (loop [index 0
@@ -323,7 +323,7 @@
 
 (def: .public (lower_cased value)
   (-> Text Text)
-  (for {@.old
+  (for [@.old
         (:as Text
              ("jvm invokevirtual:java.lang.String:toLowerCase:"
               (:as (primitive "java.lang.String") value)))
@@ -342,11 +342,11 @@
              ("lua apply" ("lua constant" "string.lower") value))
         @.ruby
         (:as Text
-             ("ruby object do" "downcase" value))}))
+             ("ruby object do" "downcase" value))]))
 
 (def: .public (upper_cased value)
   (-> Text Text)
-  (for {@.old
+  (for [@.old
         (:as Text
              ("jvm invokevirtual:java.lang.String:toUpperCase:"
               (:as (primitive "java.lang.String") value)))
@@ -365,4 +365,4 @@
              ("lua apply" ("lua constant" "string.upper") value))
         @.ruby
         (:as Text
-             ("ruby object do" "upcase" value))}))
+             ("ruby object do" "upcase" value))]))
diff --git a/stdlib/source/library/lux/data/text/buffer.lux b/stdlib/source/library/lux/data/text/buffer.lux
index af3341930..b8955f732 100644
--- a/stdlib/source/library/lux/data/text/buffer.lux
+++ b/stdlib/source/library/lux/data/text/buffer.lux
@@ -34,7 +34,7 @@
                                  ["[1]::[0]"
                                   (new [int])
                                   (toString [] java/lang/String)]))]
-  (`` (for {@.old (as_is <jvm>)
+  (`` (for [@.old (as_is <jvm>)
             @.jvm (as_is <jvm>)
             @.js (as_is (import: (JS_Array a)
                           ["[1]::[0]"
@@ -44,24 +44,24 @@
                          ...https://www.lua.org/manual/5.3/manual.html#pdf-table.concat
                          (import: (table/insert [(array.Array Text) Text] "?" Nothing))
                          ... https://www.lua.org/manual/5.3/manual.html#pdf-table.insert
-                         )}
+                         )]
            (as_is))))
 
 (`` (abstract: .public Buffer
-      (for {@.old [Nat (-> java/lang/StringBuilder java/lang/StringBuilder)]
+      (for [@.old [Nat (-> java/lang/StringBuilder java/lang/StringBuilder)]
             @.jvm [Nat (-> java/lang/StringBuilder java/lang/StringBuilder)]
             @.js [Nat (-> (JS_Array Text) (JS_Array Text))]
-            @.lua [Nat (-> (array.Array Text) (array.Array Text))]}
+            @.lua [Nat (-> (array.Array Text) (array.Array Text))]]
            ... default
            (Row Text))
 
       [(def: .public empty
          Buffer
          (:abstraction (with_expansions [<jvm> [0 function.identity]]
-                         (for {@.old <jvm>
+                         (for [@.old <jvm>
                                @.jvm <jvm>
                                @.js [0 function.identity]
-                               @.lua [0 function.identity]}
+                               @.lua [0 function.identity]]
                               ... default
                               row.empty))))
 
@@ -76,7 +76,7 @@
                                                     builder)))]
                                    (:abstraction [(n.+ (//.size chunk) capacity)
                                                   (|>> transform (then! chunk))]))]
-           (for {@.old <jvm>
+           (for [@.old <jvm>
                  @.jvm <jvm>
                  @.js (let [[capacity transform] (:representation buffer)
                             then! (: (-> (JS_Array Text) (JS_Array Text))
@@ -93,17 +93,17 @@
                                           (table/insert [array chunk])
                                           array)))]
                          (:abstraction [(n.+ (//.size chunk) capacity)
-                                        (|>> transform then!)]))}
+                                        (|>> transform then!)]))]
                 ... default
                 (|> buffer :representation (row.suffix chunk) :abstraction))))
 
        (def: .public size
          (-> Buffer Nat)
          (with_expansions [<jvm> (|>> :representation product.left)]
-           (for {@.old <jvm>
+           (for [@.old <jvm>
                  @.jvm <jvm>
                  @.js <jvm>
-                 @.lua <jvm>}
+                 @.lua <jvm>]
                 ... default
                 (|>> :representation
                      (row\mix (function (_ chunk total)
@@ -116,7 +116,7 @@
                                    (|> (java/lang/StringBuilder::new (.int capacity))
                                        transform
                                        java/lang/StringBuilder::toString))]
-           (for {@.old <jvm>
+           (for [@.old <jvm>
                  @.jvm <jvm>
                  @.js (let [[capacity transform] (:representation buffer)]
                         (|> (array.empty 0)
@@ -124,7 +124,7 @@
                             transform
                             (JS_Array::join [""])))
                  @.lua (let [[capacity transform] (:representation buffer)]
-                         (table/concat [(transform (array.empty 0)) ""]))}
+                         (table/concat [(transform (array.empty 0)) ""]))]
                 ... default
                 (row\mix (function (_ chunk total)
                            (format total chunk))
diff --git a/stdlib/source/library/lux/data/text/encoding/utf8.lux b/stdlib/source/library/lux/data/text/encoding/utf8.lux
index 19867bae4..817288316 100644
--- a/stdlib/source/library/lux/data/text/encoding/utf8.lux
+++ b/stdlib/source/library/lux/data/text/encoding/utf8.lux
@@ -15,7 +15,7 @@
                                  ["[1]::[0]"
                                   (new [[byte] java/lang/String])
                                   (getBytes [java/lang/String] [byte])]))]
-  (for {@.old (as_is <jvm>)
+  (for [@.old (as_is <jvm>)
         @.jvm (as_is <jvm>)
 
         @.js
@@ -59,12 +59,12 @@
         @.scheme
         ... https://srfi.schemers.org/srfi-140/srfi-140.html
         (as_is (ffi.import: (string->utf8 [Text] Binary))
-               (ffi.import: (utf8->string [Binary] Text)))}
+               (ffi.import: (utf8->string [Binary] Text)))]
        (as_is)))
 
 (def: (encoded value)
   (-> Text Binary)
-  (for {@.old
+  (for [@.old
         (java/lang/String::getBytes (//.name //.utf_8)
                                     ... TODO: Remove coercion below.
                                     ... The coercion below may seem
@@ -109,12 +109,12 @@
             (:as Binary))
 
         @.scheme
-        (..string->utf8 value)}))
+        (..string->utf8 value)]))
 
 (def: (decoded value)
   (-> Binary (Try Text))
   (with_expansions [<jvm> (#try.Success (java/lang/String::new value (//.name //.utf_8)))]
-    (for {@.old <jvm>
+    (for [@.old <jvm>
           @.jvm <jvm>
 
           @.js
@@ -155,7 +155,7 @@
           @.scheme
           (|> value
               ..utf8->string
-              #try.Success)})))
+              #try.Success)])))
 
 (implementation: .public codec
   (Codec Binary Text)
diff --git a/stdlib/source/library/lux/debug.lux b/stdlib/source/library/lux/debug.lux
index 8ce5e58e7..8f3245ea2 100644
--- a/stdlib/source/library/lux/debug.lux
+++ b/stdlib/source/library/lux/debug.lux
@@ -66,7 +66,7 @@
                                   (intValue [] int)
                                   (longValue [] long)
                                   (doubleValue [] double)]))]
-  (for {@.old (as_is <jvm>)
+  (for [@.old (as_is <jvm>)
         @.jvm (as_is <jvm>)
 
         @.js
@@ -114,24 +114,24 @@
                (import: (car [.Any] .Any))
                (import: (cdr [.Any] .Any))
                (import: (format [Text .Any] Text)))
-        }))
+        ]))
 
 (def: Inspector
   (.type (Format Any)))
 
-(for {@.lua (def: (tuple_array tuple)
+(for [@.lua (def: (tuple_array tuple)
               (-> (array.Array Any) (array.Array Any))
               (array.of_list
                (loop [idx 0]
                  (let [member ("lua array read" idx tuple)]
                    (if ("lua object nil?" member)
                      #.End
-                     (#.Item member (recur (++ idx))))))))}
+                     (#.Item member (recur (++ idx))))))))]
      (as_is))
 
 (def: (tuple_inspection inspection)
   (-> Inspector Inspector)
-  (with_expansions [<adaption> (for {@.lua (~~ (as_is ..tuple_array))}
+  (with_expansions [<adaption> (for [@.lua (~~ (as_is ..tuple_array))]
                                     (~~ (as_is)))]
     (`` (|>> (:as (array.Array Any))
              <adaption>
@@ -175,7 +175,7 @@
                                           (tuple_inspection inspection value)))
                                       #.None)
                                     (java/lang/Object::toString object))))]
-    (for {@.old <jvm>
+    (for [@.old <jvm>
           @.jvm <jvm>
 
           @.js
@@ -374,7 +374,7 @@
                     ... else
                     (..format ["~s" value])
                     ))
-          })))
+          ])))
 
 (exception: .public (cannot_represent_value [type Type])
   (exception.report
diff --git a/stdlib/source/library/lux/math.lux b/stdlib/source/library/lux/math.lux
index b81ca5c50..d6c85234d 100644
--- a/stdlib/source/library/lux/math.lux
+++ b/stdlib/source/library/lux/math.lux
@@ -18,7 +18,7 @@
   [tau +6.28318530717958647692]
   )
 
-(for {@.old
+(for [@.old
       (as_is (template [<name> <method>]
                [(def: .public (<name> it)
                   (-> Frac Frac)
@@ -282,7 +282,7 @@
              (def: .public root/3
                (-> Frac Frac)
                (..pow ("lux f64 /" +3.0 +1.0))))
-      })
+      ])
 
 (def: .public (round it)
   (-> Frac Frac)
diff --git a/stdlib/source/library/lux/program.lux b/stdlib/source/library/lux/program.lux
index 00e75d32c..7b81afa69 100644
--- a/stdlib/source/library/lux/program.lux
+++ b/stdlib/source/library/lux/program.lux
@@ -35,10 +35,10 @@
     (let [initialization+event_loop
           (` ((~! do) (~! io.monad)
               [(~ g!output) (~ body)
-               (~+ (for {@.old (list)
+               (~+ (for [@.old (list)
                          @.jvm (list)
                          @.js (list)
-                         @.python (list)}
+                         @.python (list)]
                         (list g!_ (` (~! thread.run!)))))]
               ((~' in) (~ g!output))))]
       (in (list (` ("lux def program"
diff --git a/stdlib/source/library/lux/target/jvm/constant.lux b/stdlib/source/library/lux/target/jvm/constant.lux
index ef1076787..d1e9b2122 100644
--- a/stdlib/source/library/lux/target/jvm/constant.lux
+++ b/stdlib/source/library/lux/target/jvm/constant.lux
@@ -71,13 +71,13 @@
   (Equivalence java/lang/Float)
 
   (def: (= parameter subject)
-    (for {@.old
+    (for [@.old
           ("jvm feq" parameter subject)
           
           @.jvm
           ("jvm float ="
            ("jvm object cast" parameter)
-           ("jvm object cast" subject))})))
+           ("jvm object cast" subject))])))
 
 (import: java/lang/Double
   ["[1]::[0]"
diff --git a/stdlib/source/library/lux/target/jvm/loader.lux b/stdlib/source/library/lux/target/jvm/loader.lux
index fe2bba2e6..1d5eda342 100644
--- a/stdlib/source/library/lux/target/jvm/loader.lux
+++ b/stdlib/source/library/lux/target/jvm/loader.lux
@@ -102,11 +102,11 @@
 
 (def: .public (memory library)
   (-> Library java/lang/ClassLoader)
-  (with_expansions [<cast> (for {@.old
+  (with_expansions [<cast> (for [@.old
                                  (<|)
                                  
                                  @.jvm
-                                 "jvm object cast"})]
+                                 "jvm object cast"])]
     (<| <cast>
         (object [] java/lang/ClassLoader []
           []
diff --git a/stdlib/source/library/lux/target/python.lux b/stdlib/source/library/lux/target/python.lux
index 4988e4d78..af0514a76 100644
--- a/stdlib/source/library/lux/target/python.lux
+++ b/stdlib/source/library/lux/target/python.lux
@@ -31,19 +31,19 @@
   (-> Text Text)
   (text.enclosed ["(" ")"]))
 
-(for {@.old (as_is (ffi.import: java/lang/CharSequence)
+(for [@.old (as_is (ffi.import: java/lang/CharSequence)
                    (ffi.import: java/lang/String
                      ["[1]::[0]"
-                      (replace [java/lang/CharSequence java/lang/CharSequence] java/lang/String)]))}
+                      (replace [java/lang/CharSequence java/lang/CharSequence] java/lang/String)]))]
      (as_is))
 
 (def: nested
   (-> Text Text)
   (.let [nested_new_line (format text.new_line text.tab)]
-    (for {@.old (|>> (format text.new_line)
+    (for [@.old (|>> (format text.new_line)
                      (:as java/lang/String)
                      (java/lang/String::replace (:as java/lang/CharSequence text.new_line)
-                                                (:as java/lang/CharSequence nested_new_line)))}
+                                                (:as java/lang/CharSequence nested_new_line)))]
          (|>> (format text.new_line)
               (text.replaced text.new_line nested_new_line)))))
 
diff --git a/stdlib/source/library/lux/time/instant.lux b/stdlib/source/library/lux/time/instant.lux
index 696b204b0..57063a5a0 100644
--- a/stdlib/source/library/lux/time/instant.lux
+++ b/stdlib/source/library/lux/time/instant.lux
@@ -152,7 +152,7 @@
 
 (def: .public now
   (IO Instant)
-  (io (..of_millis (for {@.old ("jvm invokestatic:java.lang.System:currentTimeMillis:")
+  (io (..of_millis (for [@.old ("jvm invokestatic:java.lang.System:currentTimeMillis:")
                          @.jvm (|> ("jvm member invoke static" [] "java.lang.System" "currentTimeMillis" [])
                                    ("jvm object cast")
                                    (: (primitive "java.lang.Long"))
@@ -189,7 +189,7 @@
                                            "common_lisp apply"
                                            (:as Int)
                                            (i.* +1,000))
-                         }))))
+                         ]))))
 
 (template [<field> <type> <post_processing>]
   [(def: .public (<field> instant)
diff --git a/stdlib/source/library/lux/tool/compiler/default/platform.lux b/stdlib/source/library/lux/tool/compiler/default/platform.lux
index be5d7df27..d24ad8f33 100644
--- a/stdlib/source/library/lux/tool/compiler/default/platform.lux
+++ b/stdlib/source/library/lux/tool/compiler/default/platform.lux
@@ -101,11 +101,11 @@
                                  (ioW.write system static module_id artifact_id content)))]
         (do [! ..monad]
           [_ (ioW.prepare system static module_id)
-           _ (for {@.python (|> output
+           _ (for [@.python (|> output
                                 row.list
                                 (list.sub 128)
                                 (monad.each ! (monad.each ! write_artifact!))
-                                (: (Action (List (List Any)))))}
+                                (: (Action (List (List Any)))))]
                   (|> output
                       row.list
                       (monad.each ..monad write_artifact!)
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/js.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/js.lux
index f5f47f98d..66b58bf74 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/js.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/js.lux
@@ -199,7 +199,7 @@
         [.let [inputT (type.tuple (list.repeated arity Any))]
          abstractionA (analysis/type.with_type (-> inputT Any)
                         (phase archive abstractionC))
-         _ (analysis/type.infer (for {@.js ffi.Function}
+         _ (analysis/type.infer (for [@.js ffi.Function]
                                      Any))]
         (in (#analysis.Extension extension (list (analysis.nat arity)
                                                  abstractionA)))))]))
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/lua.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/lua.lux
index dd7d43516..f7ed4ed54 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/lua.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/lua.lux
@@ -29,15 +29,15 @@
        ["[0]" phase]]]]]])
 
 (def: Nil
-  (for {@.lua ffi.Nil}
+  (for [@.lua ffi.Nil]
        Any))
 
 (def: Object
-  (for {@.lua (type (ffi.Object Any))}
+  (for [@.lua (type (ffi.Object Any))]
        Any))
 
 (def: Function
-  (for {@.lua ffi.Function}
+  (for [@.lua ffi.Function]
        Any))
 
 (def: array::new
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/php.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/php.lux
index 227bc4539..a52f8bb53 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/php.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/php.lux
@@ -108,15 +108,15 @@
           )))
 
 (def: Null
-  (for {@.php ffi.Null}
+  (for [@.php ffi.Null]
        Any))
 
 (def: Object
-  (for {@.php (type (ffi.Object Any))}
+  (for [@.php (type (ffi.Object Any))]
        Any))
 
 (def: Function
-  (for {@.php ffi.Function}
+  (for [@.php ffi.Function]
        Any))
 
 (def: object::new
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/python.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/python.lux
index 2f07f677b..700f80163 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/python.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/python.lux
@@ -108,20 +108,23 @@
           )))
 
 (def: None
-  (for {@.python
-        ffi.None}
+  (for [@.python
+        ffi.None]
        Any))
 
 (def: Object
-  (for {@.python (type (ffi.Object Any))}
+  (for [@.python
+        (type (ffi.Object Any))]
        Any))
 
 (def: Function
-  (for {@.python ffi.Function}
+  (for [@.python
+        ffi.Function]
        Any))
 
 (def: Dict
-  (for {@.python ffi.Dict}
+  (for [@.python
+        ffi.Dict]
        Any))
 
 (def: object::get
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/ruby.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/ruby.lux
index d267ca612..6bf24f1fa 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/ruby.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/ruby.lux
@@ -108,15 +108,15 @@
           )))
 
 (def: Nil
-  (for {@.ruby ffi.Nil}
+  (for [@.ruby ffi.Nil]
        Any))
 
 (def: Object
-  (for {@.ruby (type (ffi.Object Any))}
+  (for [@.ruby (type (ffi.Object Any))]
        Any))
 
 (def: Function
-  (for {@.ruby ffi.Function}
+  (for [@.ruby ffi.Function]
        Any))
 
 (def: object::get
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/scheme.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/scheme.lux
index 688803a33..2075522d7 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/scheme.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/analysis/scheme.lux
@@ -108,12 +108,12 @@
           )))
 
 (def: Nil
-  (for {@.scheme
-        ffi.Nil}
+  (for [@.scheme
+        ffi.Nil]
        Any))
 
 (def: Function
-  (for {@.scheme ffi.Function}
+  (for [@.scheme ffi.Function]
        Any))
 
 (def: bundle::object
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/generation/lua/common.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/generation/lua/common.lux
index e71de0758..1be1bcfa5 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/generation/lua/common.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/extension/generation/lua/common.lux
@@ -211,7 +211,7 @@
           (/.install "index" (trinary ..text//index))
           (/.install "size" (unary //runtime.text//size))
           ... TODO: Use version below once the Lua compiler becomes self-hosted.
-          ... (/.install "size" (unary (for {@.lua (!unary "utf8.len")}
+          ... (/.install "size" (unary (for [@.lua (!unary "utf8.len")]
           ...                               (!unary "string.len"))))
           (/.install "char" (binary ..text//char))
           (/.install "clip" (trinary ..text//clip))
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/lua/runtime.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/lua/runtime.lux
index d2b823b85..9ed2c2624 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/lua/runtime.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/lua/runtime.lux
@@ -342,7 +342,7 @@
                                                          (..char_index subject)
                                                          ..lux_index)))))]
     (with_vars [byte_index]
-      (for {@.lua <normal>}
+      (for [@.lua <normal>]
            (_.if ..on_rembulan?
              <rembulan>
              <normal>)))))
@@ -356,7 +356,7 @@
                                                       ... (_.+ (_.int +1))
                                                       (..byte_index text)
                                                       (_.- (_.int +1)))))]
-    (for {@.lua <normal>}
+    (for [@.lua <normal>]
          (_.if ..on_rembulan?
            <rembulan>
            <normal>))))
@@ -364,7 +364,7 @@
 (runtime: (text//size subject)
   (with_expansions [<rembulan> (_.return (_.apply/1 (_.var "string.len") subject))
                     <normal> (_.return (_.apply/1 (_.var "utf8.len") subject))]
-    (for {@.lua <normal>}
+    (for [@.lua <normal>]
          (_.if ..on_rembulan?
            <rembulan>
            <normal>))))
@@ -383,7 +383,7 @@
                                    (_.if (_.= _.nil offset)
                                      (_.statement (_.error/1 (_.string "[Lux Error] Cannot get char from text.")))
                                      (_.return (_.apply/2 (_.var "utf8.codepoint") text offset)))))]
-    (for {@.lua <normal>}
+    (for [@.lua <normal>]
          (_.if ..on_rembulan?
            <rembulan>
            <normal>))))
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/python/runtime.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/python/runtime.lux
index bfdf279fa..16283e2e9 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/python/runtime.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/python/runtime.lux
@@ -291,7 +291,7 @@
                   [(_.> ..i64::+limit) ..i64::+iteration ..i64::+cap ..i64::-limit]
                   [(_.< ..i64::-limit) ..i64::-iteration ..i64::-cap ..i64::+limit]
                   ))
-            (_.return (for {@.python input}
+            (_.return (for [@.python input]
                            ... This +- is only necessary to guarantee that values within the limits are always longs in Python 2
                            (|> input (_.+ ..i64::+limit) (_.- ..i64::+limit))))))))
 
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/reference.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/reference.lux
index b256823f5..4913559a1 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/reference.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/reference.lux
@@ -18,23 +18,23 @@
 ... This universe constant is for languages where one can't just turn all compiled definitions
 ... into the local variables of some scoping function.
 (def: .public universe
-  (for {... In the case of Lua, there is a limit of 200 locals in a function's scope.
+  (for [ ... In the case of Lua, there is a limit of 200 locals in a function's scope.
         @.lua (not ("lua script universe"))
         ... Cannot make all definitions be local variables because of limitations with JRuby.
         @.ruby (not ("ruby script universe"))
         ... Cannot make all definitions be local variables because of limitations with PHP itself.
         @.php (not ("php script universe"))
         ... Cannot make all definitions be local variables because of limitations with Kawa.
-        @.scheme (not ("scheme script universe"))}
+        @.scheme (not ("scheme script universe"))]
        #0))
 
 (def: universe_label
   Text
   (with_expansions [<label> (format "u" (%.nat (if ..universe 1 0)))]
-    (for {@.lua <label>
+    (for [@.lua <label>
           @.ruby <label>
           @.php <label>
-          @.scheme <label>}
+          @.scheme <label>]
          "")))
 
 (def: .public (artifact [module artifact])
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/syntax.lux b/stdlib/source/library/lux/tool/compiler/language/lux/syntax.lux
index 3df8bb802..bd1aca3b3 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/syntax.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/syntax.lux
@@ -51,7 +51,7 @@
       ["[0]" frac]]]]])
 
 (template: (inline: <declaration> <type> <body>)
-  [(for {@.python (def: <declaration> <type> <body>)}
+  [(for [@.python (def: <declaration> <type> <body>)]
         (template: <declaration> [<body>]))])
 
 ... TODO: Implement "lux syntax char case!" as a custom extension.
diff --git a/stdlib/source/library/lux/type.lux b/stdlib/source/library/lux/type.lux
index effdf2251..7c347bd0e 100644
--- a/stdlib/source/library/lux/type.lux
+++ b/stdlib/source/library/lux/type.lux
@@ -179,7 +179,8 @@
   (Equivalence Type)
   
   (def: (= x y)
-    (or (for {@.php false} ... TODO: Remove this once JPHP is gone.
+    (or (for [... TODO: Remove this once JPHP is gone.
+              @.php false]
              (same? x y))
         (case [x y]
           [(#.Primitive xname xparams) (#.Primitive yname yparams)]
diff --git a/stdlib/source/library/lux/type/check.lux b/stdlib/source/library/lux/type/check.lux
index 51bb8d13e..bf8210953 100644
--- a/stdlib/source/library/lux/type/check.lux
+++ b/stdlib/source/library/lux/type/check.lux
@@ -557,7 +557,8 @@
 ... Type-check to ensure that the 'expected' type subsumes the 'actual' type.
 (def: (check' assumptions expected actual)
   (Checker Type)
-  (if (for {@.php false} ... TODO: Remove this once JPHP is gone.
+  (if (for [... TODO: Remove this once JPHP is gone.
+            @.php false]
            (same? expected actual))
     (check\in assumptions)
     (with ..type_check_failed [expected actual]
diff --git a/stdlib/source/library/lux/world/console.lux b/stdlib/source/library/lux/world/console.lux
index a31de2fdc..e3d156adf 100644
--- a/stdlib/source/library/lux/world/console.lux
+++ b/stdlib/source/library/lux/world/console.lux
@@ -94,8 +94,8 @@
                                             
                                             (def: close
                                               (|>> (exception.except ..cannot_close) in)))))))))]
-  (for {@.old (as_is <jvm>)
-        @.jvm (as_is <jvm>)}
+  (for [@.old (as_is <jvm>)
+        @.jvm (as_is <jvm>)]
        (as_is)))
 
 (def: .public (write_line message console)
diff --git a/stdlib/source/library/lux/world/file.lux b/stdlib/source/library/lux/world/file.lux
index 9cbb0f8e4..66c125a34 100644
--- a/stdlib/source/library/lux/world/file.lux
+++ b/stdlib/source/library/lux/world/file.lux
@@ -297,7 +297,7 @@
                                                java/io/File::new
                                                (java/io/File::renameTo (java/io/File::new destination))))
                                          )))]
-  (for {@.old (as_is <for_jvm>)
+  (for [@.old (as_is <for_jvm>)
         @.jvm (as_is <for_jvm>)
 
         @.js
@@ -983,7 +983,7 @@
         ...                ..default_separator)
         ...              ))
         ...        )
-        }
+        ]
        (as_is)))
 
 (def: .public (exists? monad fs path)
diff --git a/stdlib/source/library/lux/world/file/watch.lux b/stdlib/source/library/lux/world/file/watch.lux
index d26778c03..3af235af1 100644
--- a/stdlib/source/library/lux/world/file/watch.lux
+++ b/stdlib/source/library/lux/world/file/watch.lux
@@ -456,6 +456,6 @@
                                              (async.future (..default_poll watcher)))
                                            )))))
                                )]
-  (for {@.old (as_is <jvm>)
-        @.jvm (as_is <jvm>)}
+  (for [@.old (as_is <jvm>)
+        @.jvm (as_is <jvm>)]
        (as_is)))
diff --git a/stdlib/source/library/lux/world/net/http/client.lux b/stdlib/source/library/lux/world/net/http/client.lux
index a2ec857a0..c5af6d11f 100644
--- a/stdlib/source/library/lux/world/net/http/client.lux
+++ b/stdlib/source/library/lux/world/net/http/client.lux
@@ -213,8 +213,8 @@
                                         (in [(.nat status)
                                              [#//.headers headers
                                               #//.body (..default_body input)]]))))))]
-  (for {@.old (as_is <jvm>)
-        @.jvm (as_is <jvm>)}
+  (for [@.old (as_is <jvm>)
+        @.jvm (as_is <jvm>)]
        (as_is)))
 
 (implementation: .public (async client)
diff --git a/stdlib/source/library/lux/world/program.lux b/stdlib/source/library/lux/world/program.lux
index 3203a12b1..feb95fff9 100644
--- a/stdlib/source/library/lux/world/program.lux
+++ b/stdlib/source/library/lux/world/program.lux
@@ -141,7 +141,7 @@
                                            (jvm\\consume iterator))
                                    #.End))
                                )]
-  (for {@.old (as_is <jvm>)
+  (for [@.old (as_is <jvm>)
         @.jvm (as_is <jvm>)
         @.js (as_is (def: default_exit!
                       (-> Exit (IO Nothing))
@@ -299,7 +299,7 @@
         ...        (ffi.import: (cdr [Pair] Text))
         ...        (ffi.import: (car "as" head [PList] Pair))
         ...        (ffi.import: (cdr "as" tail [PList] PList)))
-        }
+        ]
        (as_is)))
 
 (implementation: .public default
@@ -310,7 +310,7 @@
                                        java/util/Map::keySet
                                        java/util/Set::iterator
                                        ..jvm\\consume))]
-      (for {@.old <jvm>
+      (for [@.old <jvm>
             @.jvm <jvm>
             @.js (io.io (if ffi.on_node_js?
                           (case (ffi.constant Object [process env])
@@ -345,7 +345,7 @@
             ...                (let [entry (..head input)]
             ...                  (recur (..tail input)
             ...                         (dictionary.has (..car entry) (..cdr entry) output))))))
-            })))
+            ])))
 
   (def: (variable name)
     (template.let [(!fetch <method>)
@@ -358,7 +358,7 @@
                             #.None
                             (exception.except ..unknown_environment_variable [name]))))]]
       (with_expansions [<jvm> (!fetch java/lang/System::resolveEnv)]
-        (for {@.old <jvm>
+        (for [@.old <jvm>
               @.jvm <jvm>
               @.js (io.io (if ffi.on_node_js?
                             (case (do maybe.monad
@@ -374,13 +374,13 @@
               @.python (!fetch os/environ::get)
               @.lua (!fetch os/getenv)
               @.ruby (!fetch RubyEnv::fetch)
-              }))))
+              ]))))
   
   (def: home
     (io.run!
      (with_expansions [<default> (io.io "~")
                        <jvm> (io.io (maybe.else "" (java/lang/System::getProperty "user.home")))]
-       (for {@.old <jvm>
+       (for [@.old <jvm>
              @.jvm <jvm>
              @.js (if ffi.on_node_js?
                     (|> (..require [] "os")
@@ -395,7 +395,7 @@
              ...         (in (if (bit\= false (:as Bit output))
              ...                 "~"
              ...                 output)))
-             }
+             ]
             ... TODO: Replace dummy implementation.
             <default>))))
 
@@ -403,7 +403,7 @@
     (io.run!
      (with_expansions [<default> "."
                        <jvm> (io.io (maybe.else "" (java/lang/System::getProperty "user.dir")))]
-       (for {@.old <jvm>
+       (for [@.old <jvm>
              @.jvm <jvm>
              @.js (if ffi.on_node_js?
                     (case (ffi.constant ..NodeJs_Process [process])
@@ -426,7 +426,7 @@
              ...         (in (if (bit\= false (:as Bit output))
              ...                 "."
              ...                 output)))
-             }
+             ]
             ... TODO: Replace dummy implementation.
             (io.io <default>)))))
   
@@ -434,7 +434,7 @@
     (with_expansions [<jvm> (do io.monad
                               [_ (java/lang/System::exit code)]
                               (in (undefined)))]
-      (for {@.old <jvm>
+      (for [@.old <jvm>
             @.jvm <jvm>
             @.js (cond ffi.on_node_js?
                        (..exit_node_js! code)
@@ -449,4 +449,4 @@
             @.ruby (RubyKernel::exit [code])
             ... @.php (..exit [code])
             ... @.scheme (..exit [code])
-            }))))
+            ]))))
diff --git a/stdlib/source/library/lux/world/shell.lux b/stdlib/source/library/lux/world/shell.lux
index 07a9b3f3f..5c0fdfbc7 100644
--- a/stdlib/source/library/lux/world/shell.lux
+++ b/stdlib/source/library/lux/world/shell.lux
@@ -306,8 +306,8 @@
                                       process (java/lang/ProcessBuilder::start builder)]
                                      (..default_process process))))
                                )]
-  (for {@.old (as_is <jvm>)
-        @.jvm (as_is <jvm>)}
+  (for [@.old (as_is <jvm>)
+        @.jvm (as_is <jvm>)]
        (as_is)))
 
 (type: .public (Mock s)