- Moved lux/lexer and lux/lexer/regex to lux/data/text/lexer and lux/data/text/regex.

- Moved lux/pipe to lux/control/pipe.
- Moved the @pre and @post macros to lux/control/contract.
- Improved error reporting for lux/type/auto.
- Added a test for third-order type-checking for lux/type/auto.
- Fixed a bug in the tests for lux/data/coll/vector.

61 files changed, 180 insertions, 231 deletions

diff --git a/stdlib/source/lux.lux b/stdlib/source/lux.lux
index 541b4bcdc..557992ba4 100644
--- a/stdlib/source/lux.lux
+++ b/stdlib/source/lux.lux
@@ -5591,36 +5591,6 @@
     _
     (fail "Wrong syntax for :!!")))
 
-(def: #hidden hack_Text/append
-  (-> Text Text Text)
-  Text/append)
-
-(def: get-cursor
-  (Lux Cursor)
-  (lambda [state]
-    (let [{#;info info #;source    source #;modules  modules  #;scopes   scopes
-           #;type-vars types  #;host     host     #;seed   seed
-           #;expected expected #;cursor cursor
-           #;scope-type-vars scope-type-vars} state]
-      (#;Right [state cursor]))))
-
-(macro: #export (with-cursor tokens)
-  {#;doc (doc "Given some text, appends to it a prefix for identifying where the text comes from."
-              "For example:"
-              (with-cursor (format "User: " user-id))
-              "Would be the same as:"
-              (format "[the-module,the-line,the-column] " (format "User: " user-id)))}
-  (case tokens
-    (^ (list message))
-    (do Monad<Lux>
-      [cursor get-cursor]
-      (let [[module line column] cursor
-            cursor-prefix ($_ hack_Text/append "[" module "," (Nat/encode line) "," (Nat/encode column) "] ")]
-        (wrap (list (` (hack_Text/append (~ (text$ cursor-prefix)) (~ message)))))))
-    
-    _
-    (fail "Wrong syntax for @")))
-
 (macro: #export (undefined tokens)
   {#;doc (doc "Meant to be used as a stand-in for functions with undefined implementations."
               "Undefined expressions will type-check against everything, so they make good dummy implementations."
@@ -5630,45 +5600,11 @@
               "If an undefined expression is ever evaluated, it will raise an error.")}
   (case tokens
     #;Nil
-    (return (list (` (error! (with-cursor "Undefined behavior.")))))
+    (return (list (` (error! "Undefined behavior."))))
     
     _
     (fail "Wrong syntax for undefined")))
 
-(macro: #export (@pre tokens)
-  {#;doc (doc "Pre-conditions."
-              "Given a test and an expression to run, only runs the expression if the test passes."
-              "Otherwise, an error is raised."
-              (@pre (i.= 4 (i.+ 2 2))
-                    (foo 123 456 789)))}
-  (case tokens
-    (^ (list test expr))
-    (return (list (` (if (~ test)
-                       (~ expr)
-                       (error! (with-cursor (~ (text$ (Text/append "Pre-condition failed: " (ast-to-text test))))))))))
-    
-    _
-    (fail "Wrong syntax for @pre")))
-
-(macro: #export (@post tokens)
-  {#;doc (doc "Post-conditions."
-              "Given a predicate and an expression to run, evaluates the expression and then tests the output with the predicate."
-              "If the predicate returns true, returns the value of the expression."
-              "Otherwise, an error is raised."
-              (@post i.even?
-                     (i.+ 2 2)))}
-  (case tokens
-    (^ (list test expr))
-    (do Monad<Lux>
-      [g!output (gensym "")]
-      (wrap (list (` (let [(~ g!output) (~ expr)]
-                       (if ((~ test) (~ g!output))
-                         (~ g!output)
-                         (error! (with-cursor (~ (text$ (Text/append "Post-condition failed: " (ast-to-text test))))))))))))
-    
-    _
-    (fail "Wrong syntax for @post")))
-
 (macro: #export (type-of tokens)
   {#;doc (doc "Generates the type corresponding to a given definition or variable."
               (let [my-num (: Int 123)]
diff --git a/stdlib/source/lux/control/contract.lux b/stdlib/source/lux/control/contract.lux
new file mode 100644
index 000000000..2f347dfa5
--- /dev/null
+++ b/stdlib/source/lux/control/contract.lux
@@ -0,0 +1,37 @@
+(;module:
+  lux
+  (lux (control monad)
+       (data text/format)
+       [compiler #+ Monad<Lux>]
+       (macro [ast]
+              ["s" syntax #+ syntax:])))
+
+(def: #export (assert! message test)
+  (-> Text Bool [])
+  (if test
+    []
+    (error! message)))
+
+(syntax: #export (@pre test expr)
+  {#;doc (doc "Pre-conditions."
+              "Given a test and an expression to run, only runs the expression if the test passes."
+              "Otherwise, an error is raised."
+              (@pre (i.= 4 (i.+ 2 2))
+                    (foo 123 456 789)))}
+  (wrap (list (` (exec (assert! (~ (ast;text (format "Pre-condition failed: " (%ast test))))
+                                (~ test))
+                   (~ expr))))))
+
+(syntax: #export (@post test expr)
+  {#;doc (doc "Post-conditions."
+              "Given a predicate and an expression to run, evaluates the expression and then tests the output with the predicate."
+              "If the predicate returns true, returns the value of the expression."
+              "Otherwise, an error is raised."
+              (@post i.even?
+                     (i.+ 2 2)))}
+  (do @
+    [g!output (compiler;gensym "")]
+    (wrap (list (` (let [(~ g!output) (~ expr)]
+                     (exec (assert! (~ (ast;text (format "Post-condition failed: " (%ast test))))
+                                    ((~ test) (~ g!output)))
+                       (~ g!output))))))))
diff --git a/stdlib/source/lux/pipe.lux b/stdlib/source/lux/control/pipe.lux
index cfb05491d..cfb05491d 100644
--- a/stdlib/source/lux/pipe.lux
+++ b/stdlib/source/lux/control/pipe.lux
diff --git a/stdlib/source/lux/data/coll/vector.lux b/stdlib/source/lux/data/coll/vector.lux
index b0ef6aa46..1c4a1dd9d 100644
--- a/stdlib/source/lux/data/coll/vector.lux
+++ b/stdlib/source/lux/data/coll/vector.lux
@@ -15,7 +15,6 @@
        [compiler #+ with-gensyms]
        (macro [ast]
               ["s" syntax #+ syntax: Syntax])
-       [pipe]
        ))
 
 ## This implementation of vectors is based on Clojure's
diff --git a/stdlib/source/lux/data/format/json.lux b/stdlib/source/lux/data/format/json.lux
index 066777fdf..153920700 100644
--- a/stdlib/source/lux/data/format/json.lux
+++ b/stdlib/source/lux/data/format/json.lux
@@ -10,6 +10,7 @@
        (data [bool]
              [text "Text/" Eq<Text> Monoid<Text>]
              text/format
+             (text [lexer #+ Lexer Monad<Lexer>])
              [number #* "Real/" Codec<Text,Real>]
              maybe
              [char "Char/" Eq<Char> Codec<Text,Char>]
@@ -24,7 +25,7 @@
               [ast]
               [poly #+ poly:])
        [type]
-       [lexer #+ Lexer Monad<Lexer>]))
+       ))
 
 ## [Types]
 (do-template [<name> <type>]
diff --git a/stdlib/source/lux/lexer.lux b/stdlib/source/lux/data/text/lexer.lux
index e28cb0a68..e28cb0a68 100644
--- a/stdlib/source/lux/lexer.lux
+++ b/stdlib/source/lux/data/text/lexer.lux
diff --git a/stdlib/source/lux/lexer/regex.lux b/stdlib/source/lux/data/text/regex.lux
index 616f02086..21358c9b0 100644
--- a/stdlib/source/lux/lexer/regex.lux
+++ b/stdlib/source/lux/data/text/regex.lux
@@ -3,14 +3,14 @@
   (lux (control monad)
        (data [char]
              [text]
+             ["&" text/lexer #+ Lexer Monad<Lexer>]
              text/format
              [number "Int/" Codec<Text,Int>]
              [product]
              (coll [list "" Fold<List> "List/" Monad<List>]))
        [compiler #- run]
        (macro [ast]
-              ["s" syntax #+ syntax:])
-       ["&" lexer #+ Lexer Monad<Lexer>]))
+              ["s" syntax #+ syntax:])))
 
 ## [Utils]
 (def: #hidden (->Text lexer^)
diff --git a/stdlib/source/lux/type/auto.lux b/stdlib/source/lux/type/auto.lux
index fa658ffb8..7059536c3 100644
--- a/stdlib/source/lux/type/auto.lux
+++ b/stdlib/source/lux/type/auto.lux
@@ -278,11 +278,7 @@
                             (list [alt-name =deps]))))
               List/join)
       #;Nil
-      (compiler;fail (format "No alternatives."
-                             "\n"
-                             (|> alts
-                                 (List/map product;left)
-                                 (%list %ident))))
+      (compiler;fail (format "No alternatives for " (%type (type;function input-types output-type))))
 
       found
       (wrap found))))
@@ -339,7 +335,7 @@
               (::: =
                    (list;n.range +1 +10)
                    (list;n.range +1 +10))
-              "Functor map"
+              "(Functor List) map"
               (::: map n.inc (list;n.range +0 +9))
               "Caveat emptor: You need to make sure to import the module of any structure you want to use."
               "Otherwise, this macro won't find it.")}
@@ -363,8 +359,8 @@
         (compiler;fail (format "Too many options available: "
                                (|> chosen-ones
                                    (List/map (. %ident product;left))
-                                   (text;join-with ", ")
-                                   )))))
+                                   (text;join-with ", "))
+                               " --- for type: " (%type sig-type)))))
 
     (#;Right [args _])
     (do @
diff --git a/stdlib/test/test/lux/cli.lux b/stdlib/test/test/lux/cli.lux
index 8393d459b..b8ed6ca0c 100644
--- a/stdlib/test/test/lux/cli.lux
+++ b/stdlib/test/test/lux/cli.lux
@@ -1,7 +1,8 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data text/format
              [text "Text/" Eq<Text>]
              [number]
@@ -9,8 +10,7 @@
              [sum]
              (coll [list]))
        ["&" cli]
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (test: "CLI"
diff --git a/stdlib/test/test/lux/concurrency/atom.lux b/stdlib/test/test/lux/concurrency/atom.lux
index 9b6248ec8..84deafa07 100644
--- a/stdlib/test/test/lux/concurrency/atom.lux
+++ b/stdlib/test/test/lux/concurrency/atom.lux
@@ -6,8 +6,7 @@
              (coll [list "" Functor<List>])
              text/format)
        (concurrency ["&" atom])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (test: "Atoms"
diff --git a/stdlib/test/test/lux/concurrency/promise.lux b/stdlib/test/test/lux/concurrency/promise.lux
index a054e5a96..7ad25fc46 100644
--- a/stdlib/test/test/lux/concurrency/promise.lux
+++ b/stdlib/test/test/lux/concurrency/promise.lux
@@ -1,13 +1,13 @@
 (;module:
   lux
   (lux [io #- run]
-       (control monad)
+       (control monad
+                pipe)
        (data [number]
              text/format
              [error #- fail])
        (concurrency ["&" promise])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (test: "Promises"
diff --git a/stdlib/test/test/lux/concurrency/stm.lux b/stdlib/test/test/lux/concurrency/stm.lux
index d48d20a9d..d6b6c1d43 100644
--- a/stdlib/test/test/lux/concurrency/stm.lux
+++ b/stdlib/test/test/lux/concurrency/stm.lux
@@ -7,8 +7,7 @@
              text/format)
        (concurrency ["&" stm]
                     [promise])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (def: iterations/processes Int 100)
diff --git a/stdlib/test/test/lux/control/effect.lux b/stdlib/test/test/lux/control/effect.lux
index 59fc116dc..39e5afa5d 100644
--- a/stdlib/test/test/lux/control/effect.lux
+++ b/stdlib/test/test/lux/control/effect.lux
@@ -7,8 +7,7 @@
        (data [text]
              text/format)
        [macro]
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (do-template [<effect> <op> <field>]
diff --git a/stdlib/test/test/lux/control/interval.lux b/stdlib/test/test/lux/control/interval.lux
index 2127ff6df..b4c48a541 100644
--- a/stdlib/test/test/lux/control/interval.lux
+++ b/stdlib/test/test/lux/control/interval.lux
@@ -2,14 +2,14 @@
   lux
   lux/test
   (lux (control monad
+                pipe
                 ["&" interval])
        [io]
        ["R" math/random]
        (data text/format
              [number]
              ["S" coll/set]
-             ["L" coll/list])
-       pipe))
+             ["L" coll/list])))
 
 (test: "Equality."
   [bottom R;int
diff --git a/stdlib/test/test/lux/pipe.lux b/stdlib/test/test/lux/control/pipe.lux
index 08866a3f4..4687a5635 100644
--- a/stdlib/test/test/lux/pipe.lux
+++ b/stdlib/test/test/lux/control/pipe.lux
@@ -1,14 +1,14 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data text/format
              [number]
              [product]
              identity
              [text "T/" Eq<Text>])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (test: "Pipes"
diff --git a/stdlib/test/test/lux/data/char.lux b/stdlib/test/test/lux/data/char.lux
index 5025a1283..dd3c0c2da 100644
--- a/stdlib/test/test/lux/data/char.lux
+++ b/stdlib/test/test/lux/data/char.lux
@@ -1,12 +1,12 @@
 (;module:
   lux
-  (lux (control [monad])
+  (lux (control [monad]
+                pipe)
        [io]
        (data char
              [text]
              text/format)
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (test: "Char operations"
diff --git a/stdlib/test/test/lux/data/coll/array.lux b/stdlib/test/test/lux/data/coll/array.lux
index b5003f703..f7d09ae9a 100644
--- a/stdlib/test/test/lux/data/coll/array.lux
+++ b/stdlib/test/test/lux/data/coll/array.lux
@@ -1,12 +1,12 @@
 (;module:
   lux
-  (lux (control [monad])
+  (lux (control [monad]
+                pipe)
        [io]
        (data (coll ["&" array]
                    [list])
              [number])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (def: bounded-size
diff --git a/stdlib/test/test/lux/data/coll/dict.lux b/stdlib/test/test/lux/data/coll/dict.lux
index 3df06abcf..34e99cf58 100644
--- a/stdlib/test/test/lux/data/coll/dict.lux
+++ b/stdlib/test/test/lux/data/coll/dict.lux
@@ -9,8 +9,7 @@
              [char]
              (coll ["&" dict]
                    [list "List/" Fold<List> Functor<List>]))
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (test: "Dictionaries."
diff --git a/stdlib/test/test/lux/data/coll/list.lux b/stdlib/test/test/lux/data/coll/list.lux
index fe381340d..bd6f78015 100644
--- a/stdlib/test/test/lux/data/coll/list.lux
+++ b/stdlib/test/test/lux/data/coll/list.lux
@@ -1,14 +1,14 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data (coll ["&" list])
              [text "Text/" Monoid<Text>]
              [number]
              [bool]
              [product])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (def: bounded-size
diff --git a/stdlib/test/test/lux/data/coll/ordered.lux b/stdlib/test/test/lux/data/coll/ordered.lux
index ffc2bf309..c1f5c9944 100644
--- a/stdlib/test/test/lux/data/coll/ordered.lux
+++ b/stdlib/test/test/lux/data/coll/ordered.lux
@@ -7,8 +7,7 @@
                    [list "" Fold<List>])
              [number]
              text/format)
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (def: gen-nat
diff --git a/stdlib/test/test/lux/data/coll/priority-queue.lux b/stdlib/test/test/lux/data/coll/priority-queue.lux
index de885f1ee..3e28334db 100644
--- a/stdlib/test/test/lux/data/coll/priority-queue.lux
+++ b/stdlib/test/test/lux/data/coll/priority-queue.lux
@@ -4,8 +4,7 @@
        (control monad)
        (data (coll ["&" priority-queue])
              [number])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (def: (gen-queue size)
diff --git a/stdlib/test/test/lux/data/coll/queue.lux b/stdlib/test/test/lux/data/coll/queue.lux
index fac5cef12..44123f8e3 100644
--- a/stdlib/test/test/lux/data/coll/queue.lux
+++ b/stdlib/test/test/lux/data/coll/queue.lux
@@ -4,8 +4,7 @@
        (control monad)
        (data (coll ["&" queue])
              [number])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (test: "Queues"
diff --git a/stdlib/test/test/lux/data/coll/seq.lux b/stdlib/test/test/lux/data/coll/seq.lux
index 5fe3a5af1..a111ecb0e 100644
--- a/stdlib/test/test/lux/data/coll/seq.lux
+++ b/stdlib/test/test/lux/data/coll/seq.lux
@@ -1,7 +1,8 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data (coll ["&" seq]
                    ["F" tree/finger]
                    ["L" list])
@@ -10,8 +11,7 @@
              [bool]
              [product]
              maybe)
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (def: bounded-size
diff --git a/stdlib/test/test/lux/data/coll/set.lux b/stdlib/test/test/lux/data/coll/set.lux
index 2a4f05bb1..a91813675 100644
--- a/stdlib/test/test/lux/data/coll/set.lux
+++ b/stdlib/test/test/lux/data/coll/set.lux
@@ -5,8 +5,7 @@
        (data (coll ["&" set]
                    [list "" Fold<List>])
              [number])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (def: gen-nat
diff --git a/stdlib/test/test/lux/data/coll/stack.lux b/stdlib/test/test/lux/data/coll/stack.lux
index 4c44cbf06..6d26c569d 100644
--- a/stdlib/test/test/lux/data/coll/stack.lux
+++ b/stdlib/test/test/lux/data/coll/stack.lux
@@ -5,8 +5,7 @@
        (data (coll ["&" stack]
                    [list "" Fold<List>])
              [number])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (def: gen-nat
diff --git a/stdlib/test/test/lux/data/coll/stream.lux b/stdlib/test/test/lux/data/coll/stream.lux
index 2be6aa054..2ee3013e2 100644
--- a/stdlib/test/test/lux/data/coll/stream.lux
+++ b/stdlib/test/test/lux/data/coll/stream.lux
@@ -9,8 +9,7 @@
                    ["&" stream])
              [number "Nat/" Codec<Text,Nat>])
        (function [cont])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (test: "Streams"
diff --git a/stdlib/test/test/lux/data/coll/tree/rose.lux b/stdlib/test/test/lux/data/coll/tree/rose.lux
index ef43fae44..a4839c2a5 100644
--- a/stdlib/test/test/lux/data/coll/tree/rose.lux
+++ b/stdlib/test/test/lux/data/coll/tree/rose.lux
@@ -5,8 +5,7 @@
        (data (coll (tree ["&" rose])
                    [list "List/" Monad<List>])
              [number])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (def: gen-nat
diff --git a/stdlib/test/test/lux/data/coll/tree/zipper.lux b/stdlib/test/test/lux/data/coll/tree/zipper.lux
index ed0318cfe..143229dc5 100644
--- a/stdlib/test/test/lux/data/coll/tree/zipper.lux
+++ b/stdlib/test/test/lux/data/coll/tree/zipper.lux
@@ -1,15 +1,15 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data (coll [list "List/" Fold<List> Functor<List>]
                    (tree ["&" zipper]
                          [rose]))
              [text "Text/" Monoid<Text>]
              text/format
              [number])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (def: gen-tree
diff --git a/stdlib/test/test/lux/data/coll/vector.lux b/stdlib/test/test/lux/data/coll/vector.lux
index 735374c5c..6ad6934db 100644
--- a/stdlib/test/test/lux/data/coll/vector.lux
+++ b/stdlib/test/test/lux/data/coll/vector.lux
@@ -7,12 +7,11 @@
              [text "Text/" Monoid<Text>]
              text/format
              [number])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (test: "Vectors"
-  [size (|> R;nat (:: @ map (n.% +100)))
+  [size (|> R;nat (:: @ map (|>. (n.% +100) (n.max +1))))
    idx (|> R;nat (:: @ map (n.% size)))
    sample (R;vector size R;nat)
    other-sample (R;vector size R;nat)
diff --git a/stdlib/test/test/lux/data/error.lux b/stdlib/test/test/lux/data/error.lux
index 34f505142..d90387c89 100644
--- a/stdlib/test/test/lux/data/error.lux
+++ b/stdlib/test/test/lux/data/error.lux
@@ -1,10 +1,10 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data text/format
-             ["&" error])
-       pipe)
+             ["&" error]))
   lux/test)
 
 (test: "Errors"
diff --git a/stdlib/test/test/lux/data/error/exception.lux b/stdlib/test/test/lux/data/error/exception.lux
index 41d01077e..bc84df7f5 100644
--- a/stdlib/test/test/lux/data/error/exception.lux
+++ b/stdlib/test/test/lux/data/error/exception.lux
@@ -7,8 +7,7 @@
              [text]
              text/format
              [number])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (exception: Some-Exception)
diff --git a/stdlib/test/test/lux/data/format/json.lux b/stdlib/test/test/lux/data/format/json.lux
index ad70d5c0e..37fe49786 100644
--- a/stdlib/test/test/lux/data/format/json.lux
+++ b/stdlib/test/test/lux/data/format/json.lux
@@ -3,7 +3,8 @@
   (lux [io]
        (control monad
                 codec
-                eq)
+                eq
+                pipe)
        (data [text "Text/" Monoid<Text>]
              text/format
              [error #- fail]
@@ -21,7 +22,6 @@
               [syntax #+ syntax:]
               [poly #+ derived:])
        ["R" math/random]
-       pipe
        test)
   )
 
diff --git a/stdlib/test/test/lux/data/ident.lux b/stdlib/test/test/lux/data/ident.lux
index f88693003..07aaf8d0a 100644
--- a/stdlib/test/test/lux/data/ident.lux
+++ b/stdlib/test/test/lux/data/ident.lux
@@ -1,12 +1,12 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data ["&" ident]
              [text "Text/" Eq<Text>]
              text/format)
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (def: (gen-part size)
diff --git a/stdlib/test/test/lux/data/log.lux b/stdlib/test/test/lux/data/log.lux
index 40a124490..ea174fc6b 100644
--- a/stdlib/test/test/lux/data/log.lux
+++ b/stdlib/test/test/lux/data/log.lux
@@ -1,12 +1,12 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data ["&" log]
              [text "Text/" Monoid<Text> Eq<Text>]
              [number]
-             [product])
-       pipe)
+             [product]))
   lux/test)
 
 (test: "Logs"
diff --git a/stdlib/test/test/lux/data/maybe.lux b/stdlib/test/test/lux/data/maybe.lux
index 07961a6d0..8cfb4c38f 100644
--- a/stdlib/test/test/lux/data/maybe.lux
+++ b/stdlib/test/test/lux/data/maybe.lux
@@ -1,11 +1,11 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data ["&" maybe]
              [text "Text/" Monoid<Text>]
-             [number])
-       pipe)
+             [number]))
   lux/test)
 
 (test: "Maybe"
diff --git a/stdlib/test/test/lux/data/number.lux b/stdlib/test/test/lux/data/number.lux
index ad89649ba..eefbd584b 100644
--- a/stdlib/test/test/lux/data/number.lux
+++ b/stdlib/test/test/lux/data/number.lux
@@ -1,12 +1,12 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data number
              [text "Text/" Monoid<Text> Eq<Text>]
              text/format)
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (do-template [category rand-gen <Eq> <Order>]
diff --git a/stdlib/test/test/lux/data/number/complex.lux b/stdlib/test/test/lux/data/number/complex.lux
index 8ed27680c..9555c031e 100644
--- a/stdlib/test/test/lux/data/number/complex.lux
+++ b/stdlib/test/test/lux/data/number/complex.lux
@@ -1,7 +1,8 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data [text "Text/" Monoid<Text>]
              text/format
              [bool "b/" Eq<Bool>]
@@ -10,8 +11,7 @@
              (coll [list "List/" Fold<List> Functor<List>])
              [product])
        [math]
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 ## Based on org.apache.commons.math4.complex.Complex
diff --git a/stdlib/test/test/lux/data/number/ratio.lux b/stdlib/test/test/lux/data/number/ratio.lux
index c1f7e104f..7ae36e573 100644
--- a/stdlib/test/test/lux/data/number/ratio.lux
+++ b/stdlib/test/test/lux/data/number/ratio.lux
@@ -1,7 +1,8 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data [text "Text/" Monoid<Text>]
              text/format
              [bool "b/" Eq<Bool>]
@@ -9,8 +10,7 @@
              ["&" number/ratio "&/" Number<Ratio>]
              (coll [list "List/" Fold<List> Functor<List>])
              [product])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (def: gen-part
diff --git a/stdlib/test/test/lux/data/sum.lux b/stdlib/test/test/lux/data/sum.lux
index 8ab124c1b..389ff1b9e 100644
--- a/stdlib/test/test/lux/data/sum.lux
+++ b/stdlib/test/test/lux/data/sum.lux
@@ -1,12 +1,12 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data sum
              [text "Text/" Monoid<Text>]
              [number]
-             (coll [list]))
-       pipe)
+             (coll [list])))
   lux/test)
 
 (test: "Sum operations"
diff --git a/stdlib/test/test/lux/data/text.lux b/stdlib/test/test/lux/data/text.lux
index 4563d9b12..f306778ba 100644
--- a/stdlib/test/test/lux/data/text.lux
+++ b/stdlib/test/test/lux/data/text.lux
@@ -1,14 +1,14 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data ["&" text]
              [char]
              text/format
              [number]
              (coll [list]))
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (test: "Size"
diff --git a/stdlib/test/test/lux/lexer.lux b/stdlib/test/test/lux/data/text/lexer.lux
index 0bfd8dec7..92aeca0d8 100644
--- a/stdlib/test/test/lux/lexer.lux
+++ b/stdlib/test/test/lux/data/text/lexer.lux
@@ -1,15 +1,15 @@
 (;module:
   lux
-  (lux (control monad)
+  (lux (control monad
+                pipe)
        [io]
        (data [error #- fail]
              [text "T/" Eq<Text>]
              text/format
+             ["&" text/lexer]
              [char "C/" Eq<Char>]
              (coll [list]))
-       ["R" math/random]
-       pipe
-       ["&" lexer])
+       ["R" math/random])
   lux/test)
 
 ## [Utils]
diff --git a/stdlib/test/test/lux/lexer/regex.lux b/stdlib/test/test/lux/data/text/regex.lux
index 1a21111f8..e737d5ee4 100644
--- a/stdlib/test/test/lux/lexer/regex.lux
+++ b/stdlib/test/test/lux/data/text/regex.lux
@@ -1,18 +1,18 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data [error #- fail]
              [product]
              [text "T/" Eq<Text>]
-             text/format)
+             text/format
+             (text [lexer]
+                   ["&" regex]))
        [compiler]
        (macro [ast]
               ["s" syntax #+ syntax:])
-       ["R" math/random]
-       pipe
-       [lexer]
-       (lexer ["&" regex]))
+       ["R" math/random])
   lux/test)
 
 ## [Utils]
diff --git a/stdlib/test/test/lux/function/cont.lux b/stdlib/test/test/lux/function/cont.lux
index ba1224bb8..c2e36a06b 100644
--- a/stdlib/test/test/lux/function/cont.lux
+++ b/stdlib/test/test/lux/function/cont.lux
@@ -7,8 +7,7 @@
              [number]
              [product])
        (function ["&" cont])
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (test: "Continuations"
diff --git a/stdlib/test/test/lux/function/reader.lux b/stdlib/test/test/lux/function/reader.lux
index 14b95af94..602efc603 100644
--- a/stdlib/test/test/lux/function/reader.lux
+++ b/stdlib/test/test/lux/function/reader.lux
@@ -1,12 +1,12 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data [text "Text/" Monoid<Text>]
              text/format
              [number])
-       (function ["&" reader])
-       pipe)
+       (function ["&" reader]))
   lux/test)
 
 (test: "Readers"
diff --git a/stdlib/test/test/lux/function/state.lux b/stdlib/test/test/lux/function/state.lux
index 186b786e0..9ef61e4d3 100644
--- a/stdlib/test/test/lux/function/state.lux
+++ b/stdlib/test/test/lux/function/state.lux
@@ -1,13 +1,13 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data [text "Text/" Monoid<Text>]
              text/format
              [number]
              [product])
-       (function ["&" state])
-       pipe)
+       (function ["&" state]))
   lux/test)
 
 (test: "State"
diff --git a/stdlib/test/test/lux/function/thunk.lux b/stdlib/test/test/lux/function/thunk.lux
index e3e9aca1b..753398f77 100644
--- a/stdlib/test/test/lux/function/thunk.lux
+++ b/stdlib/test/test/lux/function/thunk.lux
@@ -3,7 +3,6 @@
   (lux [io]
        (control monad)
        (function ["&" thunk])
-       pipe
        ["R" math/random])
   lux/test)
 
diff --git a/stdlib/test/test/lux/host.js.lux b/stdlib/test/test/lux/host.js.lux
index 7d79b2b87..b7dbe043f 100644
--- a/stdlib/test/test/lux/host.js.lux
+++ b/stdlib/test/test/lux/host.js.lux
@@ -4,8 +4,7 @@
        (control monad)
        (data text/format)
        ["&" host]
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (test: "JavaScript operations"
diff --git a/stdlib/test/test/lux/host.jvm.lux b/stdlib/test/test/lux/host.jvm.lux
index f58b706d5..4bd96ad62 100644
--- a/stdlib/test/test/lux/host.jvm.lux
+++ b/stdlib/test/test/lux/host.jvm.lux
@@ -1,14 +1,14 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data text/format
              [number]
              [product]
              [text "Text/" Eq<Text>])
        ["&" host #+ jvm-import class: interface: object]
-       ["R" math/random]
-       pipe)
+       ["R" math/random])
   lux/test)
 
 (jvm-import java.lang.Exception
diff --git a/stdlib/test/test/lux/macro/ast.lux b/stdlib/test/test/lux/macro/ast.lux
index 768dafbf8..95ac999a0 100644
--- a/stdlib/test/test/lux/macro/ast.lux
+++ b/stdlib/test/test/lux/macro/ast.lux
@@ -6,7 +6,6 @@
              text/format
              [number])
        ["R" math/random]
-       pipe
        (macro ["&" ast]))
   lux/test)
 
diff --git a/stdlib/test/test/lux/macro/poly/eq.lux b/stdlib/test/test/lux/macro/poly/eq.lux
index c2f9c0ac1..3cd515fc6 100644
--- a/stdlib/test/test/lux/macro/poly/eq.lux
+++ b/stdlib/test/test/lux/macro/poly/eq.lux
@@ -9,7 +9,6 @@
              [char]
              [text])
        ["R" math/random]
-       pipe
        [macro]
        (macro [poly #+ derived:]
               ["&" poly/eq]))
diff --git a/stdlib/test/test/lux/macro/poly/functor.lux b/stdlib/test/test/lux/macro/poly/functor.lux
index b98d75c7a..3294556a4 100644
--- a/stdlib/test/test/lux/macro/poly/functor.lux
+++ b/stdlib/test/test/lux/macro/poly/functor.lux
@@ -10,7 +10,6 @@
              [char]
              [text])
        ["R" math/random]
-       pipe
        [macro]
        (macro [poly #+ derived:]
               ["&" poly/functor]))
diff --git a/stdlib/test/test/lux/macro/poly/text-encoder.lux b/stdlib/test/test/lux/macro/poly/text-encoder.lux
index ec312e62b..ec392fc8e 100644
--- a/stdlib/test/test/lux/macro/poly/text-encoder.lux
+++ b/stdlib/test/test/lux/macro/poly/text-encoder.lux
@@ -9,7 +9,6 @@
              [char]
              [text])
        ["R" math/random]
-       pipe
        [macro]
        (macro [poly #+ derived:]
               ["&" poly/text-encoder]))
diff --git a/stdlib/test/test/lux/macro/syntax.lux b/stdlib/test/test/lux/macro/syntax.lux
index b9dd304e1..11d456236 100644
--- a/stdlib/test/test/lux/macro/syntax.lux
+++ b/stdlib/test/test/lux/macro/syntax.lux
@@ -11,7 +11,6 @@
              [ident]
              [error #- fail])
        ["R" math/random]
-       pipe
        [compiler]
        (macro [ast]
               ["s" syntax #+ syntax: Syntax]))
diff --git a/stdlib/test/test/lux/math.lux b/stdlib/test/test/lux/math.lux
index 4d8b8d12a..2b834b9cc 100644
--- a/stdlib/test/test/lux/math.lux
+++ b/stdlib/test/test/lux/math.lux
@@ -9,7 +9,6 @@
              (coll [list "List/" Fold<List> Functor<List>])
              [product])
        ["R" math/random]
-       pipe
        ["&" math])
   lux/test)
 
diff --git a/stdlib/test/test/lux/math/logic/continuous.lux b/stdlib/test/test/lux/math/logic/continuous.lux
index fa08ec864..b1770c815 100644
--- a/stdlib/test/test/lux/math/logic/continuous.lux
+++ b/stdlib/test/test/lux/math/logic/continuous.lux
@@ -3,7 +3,6 @@
   (lux [io]
        (control monad)
        ["R" math/random]
-       pipe
        ["&" math/logic/continuous])
   lux/test)
 
diff --git a/stdlib/test/test/lux/math/logic/fuzzy.lux b/stdlib/test/test/lux/math/logic/fuzzy.lux
index afcd8b731..284fffa4b 100644
--- a/stdlib/test/test/lux/math/logic/fuzzy.lux
+++ b/stdlib/test/test/lux/math/logic/fuzzy.lux
@@ -8,7 +8,6 @@
              [number]
              text/format)
        ["R" math/random]
-       pipe
        (math/logic ["&" fuzzy]
                    continuous))
   lux/test)
diff --git a/stdlib/test/test/lux/math/simple.lux b/stdlib/test/test/lux/math/simple.lux
index 32f5fb20c..9aec7f1fc 100644
--- a/stdlib/test/test/lux/math/simple.lux
+++ b/stdlib/test/test/lux/math/simple.lux
@@ -9,7 +9,6 @@
              (coll [list "List/" Fold<List> Functor<List>])
              [product])
        ["R" math/random]
-       pipe
        ["&" math/simple])
   lux/test)
 
diff --git a/stdlib/test/test/lux/type.lux b/stdlib/test/test/lux/type.lux
index e9401c738..d1098b960 100644
--- a/stdlib/test/test/lux/type.lux
+++ b/stdlib/test/test/lux/type.lux
@@ -1,14 +1,14 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control monad
+                pipe)
        (data [text "Text/" Monoid<Text>]
              text/format
              [number]
              maybe
              (coll [list]))
        ["R" math/random]
-       pipe
        ["&" type])
   lux/test)
 
diff --git a/stdlib/test/test/lux/type/auto.lux b/stdlib/test/test/lux/type/auto.lux
index 536e3b851..c7e321240 100644
--- a/stdlib/test/test/lux/type/auto.lux
+++ b/stdlib/test/test/lux/type/auto.lux
@@ -11,7 +11,6 @@
              maybe
              (coll [list]))
        ["R" math/random]
-       pipe
        [type]
        type/auto)
   lux/test)
@@ -32,4 +31,9 @@
               (::: =
                    (list;n.range +1 +10)
                    (list;n.range +1 +10)))
+
+      (assert "Can automatically select third-order structures."
+              (let [lln (::: map (list;n.range +1)
+                             (list;n.range +1 +10))]
+                (::: = lln lln)))
       ))
diff --git a/stdlib/test/test/lux/type/check.lux b/stdlib/test/test/lux/type/check.lux
index 47904c41b..d76a53622 100644
--- a/stdlib/test/test/lux/type/check.lux
+++ b/stdlib/test/test/lux/type/check.lux
@@ -8,7 +8,6 @@
              maybe
              (coll [list]))
        ["R" math/random]
-       pipe
        [type]
        ["&" type/check])
   lux/test)
diff --git a/stdlib/test/tests.lux b/stdlib/test/tests.lux
index c773b3f17..6b23caebd 100644
--- a/stdlib/test/tests.lux
+++ b/stdlib/test/tests.lux
@@ -9,9 +9,6 @@
         (lux ["_;" cli]
              ["_;" host]
              ["_;" io]
-             ["_;" pipe]
-             ["_;" lexer]
-             (lexer ["_;" regex])
              (function ["_;" cont]
                        ["_;" reader]
                        ["_;" state]
@@ -22,45 +19,44 @@
                           ["_;" promise]
                           ["_;" stm])
              (control ["_;" effect]
-                      ["_;" interval])
-             (data [bit]
-                   [bool]
-                   [char]
-                   [error]
-                   [ident]
-                   [identity]
-                   [log]
-                   [maybe]
-                   [number]
+                      ["_;" interval]
+                      ["_;" pipe])
+             (data ["_;" bit]
+                   ["_;" bool]
+                   ["_;" char]
+                   ["_;" error]
+                   ["_;" ident]
+                   ["_;" identity]
+                   ["_;" log]
+                   ["_;" maybe]
+                   ["_;" number]
                    (number ["_;" ratio]
                            ["_;" complex])
-                   [product]
-                   [sum]
-                   [text]
-                   (error [exception])
-                   (format [json])
-                   (coll [array]
-                         [dict]
-                         [list]
-                         [queue]
-                         [set]
-                         [ordered]
-                         [stack]
-                         ## [vector]
-                         (tree [rose]
-                               [zipper])
+                   ["_;" product]
+                   ["_;" sum]
+                   ["_;" text]
+                   (error ["_;" exception])
+                   (format ["_;" json])
+                   (coll ["_;" array]
+                         ["_;" dict]
+                         ["_;" list]
+                         ["_;" queue]
+                         ["_;" set]
+                         ["_;" ordered]
+                         ["_;" stack]
+                         ["_;" vector]
+                         (tree ["_;" rose]
+                               ["_;" zipper])
                          ["_;" seq]
                          ["_;" priority-queue]
                          ["_;" stream])
-                   (text [format])
-                   )
+                   (text ["_;" format]
+                         ["_;" lexer]
+                         ["_;" regex]))
              ["_;" math]
              (math ["_;" simple]
                    (logic ["_;" continuous]
-                          ["_;" fuzzy])
-                   ## ["_;" random]
-                   )
-             ## ["_;" macro]
+                          ["_;" fuzzy]))
              (macro ["_;" ast]
                     ["_;" syntax]
                     (poly ["poly_;" eq]
@@ -69,7 +65,13 @@
              ["_;" type]
              (type ["_;" check]
                    ["_;" auto])
-             )))
+             ))
+  (lux (control [contract])
+       (data [env]
+             [trace]
+             [store])
+       [macro]
+       (math [random])))
 
 ## [Program]
 (program: args