Generalized macro-let.

15 files changed, 99 insertions, 24 deletions

diff --git a/stdlib/source/library/lux/macro/local.lux b/stdlib/source/library/lux/macro/local.lux
index a921afee1..5a07b4a48 100644
--- a/stdlib/source/library/lux/macro/local.lux
+++ b/stdlib/source/library/lux/macro/local.lux
@@ -1,12 +1,14 @@
 (.using
  [library
-  [lux (.except)
+  [lux (.except with let)
    ["[0]" meta]
    [abstract
     ["[0]" monad (.only do)]]
    [control
     ["[0]" try (.only Try)]
-    ["[0]" exception (.only exception:)]]
+    ["[0]" exception (.only exception:)]
+    ["<>" parser (.only)
+     ["<[0]>" code]]]
    [data
     ["[0]" product]
     ["[0]" text]
@@ -15,6 +17,7 @@
      [dictionary
       ["[0]" plist (.only PList)]]]]]]
  ["[0]" // (.only)
+  [syntax (.only syntax)]
   ["[1][0]" code]])
 
 (exception: .public (unknown_module [module Text])
@@ -102,7 +105,41 @@
     [_ (monad.each meta.monad ..push_one macros)
      seed meta.seed
      g!pop (//.symbol "pop")
-     _ (let [g!pop (is Symbol
-                       ["" (//code.format g!pop)])]
+     _ (.let [g!pop (is Symbol
+                        ["" (//code.format g!pop)])]
          (..push_one [g!pop (..pop_all (list#each product.left macros) g!pop)]))]
     (in (` ((~ g!pop))))))
+
+(def: .public (with macros body)
+  (-> (List [Symbol Macro]) Code (Meta (List Code)))
+  (do [! meta.monad]
+    [expression? (is (Meta Bit)
+                     (function (_ lux)
+                       {try.#Success [lux (case (the .#expected lux)
+                                            {.#None}
+                                            false
+
+                                            {.#Some _}
+                                            true)]}))
+     g!pop (..push macros)]
+    (.if expression?
+      (//.with_symbols [g!body]
+        (in (list (` (.let [(~ g!body) (~ body)]
+                       (exec
+                         (~ g!pop)
+                         (~ g!body)))))))
+      (in (list body
+                g!pop)))))
+
+(def: .public let
+  (syntax (_ [locals (<code>.tuple (<>.some (<>.and <code>.local <code>.any)))
+              body <code>.any])
+    (do [! meta.monad]
+      [here_name meta.current_module_name
+       locals (monad.each ! (function (_ [name value])
+                              (|> value
+                                  (meta.eval .Macro)
+                                  (at ! each (|>> (as .Macro)
+                                                  [[here_name name]]))))
+                          locals)]
+      (..with locals body))))
diff --git a/stdlib/source/library/lux/macro/template.lux b/stdlib/source/library/lux/macro/template.lux
index 439c99a3a..2251051d5 100644
--- a/stdlib/source/library/lux/macro/template.lux
+++ b/stdlib/source/library/lux/macro/template.lux
@@ -157,6 +157,7 @@
          #parameters parameters
          #template template])))
 
+... TODO: Get rid of this (and any local definitions it depends on) once the bootstrapping compiler is gone.
 (def: .public let
   (syntax (_ [locals (<code>.tuple (<>.some ..local))
               body <code>.any])
diff --git a/stdlib/source/library/lux/target/jvm/type/parser.lux b/stdlib/source/library/lux/target/jvm/type/parser.lux
index 53bd29aa0..aa64e4334 100644
--- a/stdlib/source/library/lux/target/jvm/type/parser.lux
+++ b/stdlib/source/library/lux/target/jvm/type/parser.lux
@@ -18,7 +18,7 @@
   [category (.only Void Value Return Method Primitive Object Class Array Var Parameter Declaration)]
   ["[1][0]" signature]
   ["[1][0]" descriptor]
-  ["[0]" // (.only)
+  [//
    [encoding
     ["[1][0]" name (.only External)]]]])
 
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 d477f443e..8342ce912 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
@@ -5,16 +5,16 @@
    [abstract
     ["[0]" monad (.only do)]]
    [control
-    ["<>" parser
+    ["<>" parser (.only)
      ["<[0]>" code (.only Parser)]]]
    [data
     [collection
      ["[0]" array]
      ["[0]" dictionary]
      ["[0]" list]]]
-   ["[0]" type
+   ["[0]" type (.only)
     ["[0]" check]]
-   ["@" target
+   ["@" target (.only)
     ["_" js]]]]
  [//
   ["/" lux (.only custom)]
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 428ea1068..fa08d5be0 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
@@ -5,16 +5,16 @@
    [abstract
     ["[0]" monad (.only do)]]
    [control
-    ["<>" parser
+    ["<>" parser (.only)
      ["<[0]>" code (.only Parser)]]]
    [data
     [collection
      ["[0]" array]
      ["[0]" dictionary]
      ["[0]" list]]]
-   ["[0]" type
+   ["[0]" type (.only)
     ["[0]" check]]
-   ["@" target
+   ["@" target (.only)
     ["_" lua]]]]
  [//
   ["/" lux (.only custom)]
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 3defef9c9..aa2944967 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
@@ -5,16 +5,16 @@
    [abstract
     ["[0]" monad (.only do)]]
    [control
-    ["<>" parser
+    ["<>" parser (.only)
      ["<[0]>" code (.only Parser)]]]
    [data
     [collection
      ["[0]" array]
      ["[0]" dictionary]
      ["[0]" list]]]
-   ["[0]" type
+   ["[0]" type (.only)
     ["[0]" check]]
-   ["@" target
+   ["@" target (.only)
     ["_" python]]]]
  [//
   ["/" lux (.only custom)]
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 4678fe9e1..01895a3e7 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
@@ -5,16 +5,16 @@
    [abstract
     ["[0]" monad (.only do)]]
    [control
-    ["<>" parser
+    ["<>" parser (.only)
      ["<[0]>" code (.only Parser)]]]
    [data
     [collection
      ["[0]" array]
      ["[0]" dictionary]
      ["[0]" list]]]
-   ["[0]" type
+   ["[0]" type (.only)
     ["[0]" check]]
-   ["@" target
+   ["@" target (.only)
     ["_" ruby]]]]
  [//
   ["/" lux (.only custom)]
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/jvm/case.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/jvm/case.lux
index e96a88889..3ab3c67f7 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/jvm/case.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/jvm/case.lux
@@ -35,7 +35,7 @@
     [access
      ["[0]" member (.only Member)]]]
    [///
-    ["[0]" phase ("operation#[0]" monad)]
+    ["[0]" phase (.open: "operation#[0]" monad)]
     [reference
      [variable (.only Register)]]]]])
 
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/jvm/function.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/jvm/function.lux
index e9f9b5800..3de519160 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/jvm/function.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/jvm/function.lux
@@ -1,6 +1,6 @@
 (.using
  [library
-  [lux (.except Type Label)
+  [lux (.except Type Label with)
    [abstract
     ["[0]" monad (.only do)]]
    [data
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/jvm/reference.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/jvm/reference.lux
index 7f6ade8c6..21b5a57b4 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/jvm/reference.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/jvm/reference.lux
@@ -20,7 +20,7 @@
    [//
     ["[0]" generation]
     [///
-     ["[1]" phase ("operation#[0]" monad)]
+     ["[1]" phase (.open: "operation#[0]" monad)]
      [reference
       ["[0]" variable (.only Register Variable)]]
      [meta
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/lua.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/lua.lux
index e14772296..669e1667b 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/lua.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/lua.lux
@@ -20,7 +20,7 @@
   ["/[1]" //
    ["[1][0]" reference]
    ["/[1]" //
-    ["[1][0]" extension
+    ["[1][0]" extension (.only)
      [generation
       [lua
        ["[1]/[0]" common]]]]
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 503638aeb..8898da66d 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
@@ -1,6 +1,6 @@
 (.using
  [library
-  [lux (.except Label Location)
+  [lux (.except Label Location left right)
    ["[0]" meta]
    [abstract
     ["[0]" monad (.only do)]]
diff --git a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/python.lux b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/python.lux
index 054e84344..a0c15f71e 100644
--- a/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/python.lux
+++ b/stdlib/source/library/lux/tool/compiler/language/lux/phase/generation/python.lux
@@ -20,7 +20,7 @@
   ["/[1]" //
    ["[1][0]" reference]
    ["/[1]" //
-    ["[1][0]" extension
+    ["[1][0]" extension (.only)
      [generation
       [python
        ["[1]/[0]" common]]]]
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 12d1f65c7..c0101452a 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
@@ -1,6 +1,6 @@
 (.using
  [library
-  [lux (.except ++)
+  [lux (.except ++ left right)
    [abstract
     ["[0]" monad (.only do)]]
    [control
diff --git a/stdlib/source/test/lux/macro/local.lux b/stdlib/source/test/lux/macro/local.lux
index de1073f55..bb03574a1 100644
--- a/stdlib/source/test/lux/macro/local.lux
+++ b/stdlib/source/test/lux/macro/local.lux
@@ -27,6 +27,12 @@
  [\\library
   ["[0]" /]])
 
+(/.let [!pow/2 (template (_ <scalar>)
+                 [(n.* <scalar> <scalar>)])]
+  (def: pow/2
+    (-> Nat Nat)
+    (|>> !pow/2)))
+
 (def: macro_error
   (syntax (_ [macro <code>.any])
     (function (_ compiler)
@@ -90,4 +96,35 @@
                                  (<| ..macro_error
                                      (..with ["" "actual"] expected #1)
                                      (n.= expected (..actual)))))
+             (do !
+               [scalar random.nat]
+               (_.coverage [/.let]
+                 (let [can_use_with_statements!
+                       (n.= (all n.* scalar scalar)
+                            (..pow/2 scalar))]
+                   (and can_use_with_statements!
+                        (/.let [pow/3 (template (_ <scalar>)
+                                        [(all n.* <scalar> <scalar> <scalar>)])
+                                pow/9 (template (_ <scalar>)
+                                        [(pow/3 (pow/3 <scalar>))])]
+                          (let [can_use_with_expressions!
+                                (n.= (all n.* scalar scalar scalar)
+                                     (pow/3 scalar))
+
+                                can_refer!
+                                (n.= (all n.*
+                                          scalar scalar scalar
+                                          scalar scalar scalar
+                                          scalar scalar scalar)
+                                     (pow/9 scalar))
+
+                                can_shadow!
+                                (let [pow/3 (function (_ scalar)
+                                              (all n.+ scalar scalar scalar))]
+                                  (n.= (all n.+ scalar scalar scalar)
+                                       (pow/3 scalar)))]
+                            (and can_use_with_expressions!
+                                 can_refer!
+                                 can_shadow!)))
+                        ))))
              ))))