no more @registry juggling

9 files changed, 130 insertions, 129 deletions

diff --git a/copilot.moon b/copilot.moon
index 0d562f3..78848e5 100644
--- a/copilot.moon
+++ b/copilot.moon
@@ -28,24 +28,14 @@ class Copilot
       L\error "error parsing: #{err}"
       return
 
-    ok, err = pcall @registry\prepare
-    if not ok
-      L\error "error preparing: #{err}"
-      return
-
     scope = Scope ast, globals
-    ok, err = pcall ast\eval, scope, @registry
+    ok, err = pcall (@registry\wrap ast\eval), scope, @registry
     if not ok
       L\error "error evaluating: #{err}"
       return
 
     @root = err
 
-    ok, err = pcall @registry\finalize
-    if not ok
-      L\error "error finalizing: #{err}"
-      return
-
     spit @file, ast\stringify!
 
   update: (dt) =>
diff --git a/core/base.moon b/core/base.moon
index 3be2a98..dcf600a 100644
--- a/core/base.moon
+++ b/core/base.moon
@@ -23,7 +23,6 @@ class Op
 class Action
 -- common
   new: (head, @tag) =>
-    @registry = @tag.registry -- @TODO: remove
     @patch head
 
 -- AST interface
diff --git a/core/builtin.moon b/core/builtin.moon
index 833f7a0..97f4457 100644
--- a/core/builtin.moon
+++ b/core/builtin.moon
@@ -12,7 +12,7 @@ prints the docstring for sym in the console"
   eval: (scope, tail) =>
     assert #tail == 1, "'doc' takes exactly one parameter"
 
-    def = L\push tail[1]\eval, scope, @registry
+    def = L\push tail[1]\eval, scope
     L\print "(doc #{tail[1]\stringify!}):\n#{def\getc!.doc}\n"
     nil
 
@@ -31,9 +31,9 @@ updates all val-exprs."
     values = L\push ->
       return for i=1,#tail,2
         name, val_expr = tail[i], tail[i+1]
-        name = (name\quote scope, @registry)\getc 'sym'
+        name = (name\quote scope)\getc 'sym'
 
-        val = val_expr\eval scope, @registry
+        val = val_expr\eval scope
         scope\set name, Const.wrap_ref val
         val
 
@@ -48,7 +48,7 @@ all scopes have to be eval-time constants."
   eval: (scope, tail) =>
     L\trace "evaling #{@}"
     for child in *tail
-      value = L\push child\eval, scope, @registry
+      value = L\push child\eval, scope
       L\trace @, "merging #{value} into #{scope}"
       assert value.type == 'scope', "'use' only works on scopes"
       scope\use value\getc 'scope'
@@ -65,7 +65,7 @@ name-str has to be an eval-time constant."
     L\trace "evaling #{@}"
     assert #tail == 1, "'require' takes exactly one parameter"
 
-    name = L\push tail[1]\eval, scope, @registry
+    name = L\push tail[1]\eval, scope
 
     L\trace @, "loading module #{name}"
     Const.wrap require "lib.#{name\getc 'str'}"
@@ -81,7 +81,7 @@ requires modules sym1, sym2, ... and defines them as sym1, sym2, ... in the curr
 
 
     for child in *tail
-      name = (child\quote scope, @registry)\getc 'sym'
+      name = (child\quote scope)\getc 'sym'
       scope\set name, Const.wrap require "lib.#{name}"
 
     nil
@@ -97,7 +97,7 @@ requires modules sym1, sym2, ... and merges them into the current scope"
 
 
     for child in *tail
-      name = (child\quote scope, @registry)\getc 'sym'
+      name = (child\quote scope)\getc 'sym'
       scope\use (Const.wrap require "lib.#{name}")\getc 'scope'
 
     nil
@@ -115,9 +115,9 @@ the symbols p1, p2, ... will resolve to the arguments passed to the function."
     assert params.__class == Cell, "'fn's first argument has to be an expression"
     param_symbols = for param in *params.children
       assert param.type == 'sym', "function parameter declaration has to be a symbol"
-      param\quote scope, @registry
+      param\quote scope
 
-    body = body\quote scope, @registry
+    body = body\quote scope
     Const.wrap FnDef param_symbols, body, scope
 
 class defn extends Action
@@ -130,13 +130,13 @@ declares a lambda (see (doc fn)) and defines it in the current scope"
     assert #tail == 3, "'defn' takes exactly three arguments"
     { name, params, body } = tail
 
-    name = (name\quote scope, @registry)\getc 'sym'
+    name = (name\quote scope)\getc 'sym'
     assert params.__class == Cell, "'defn's second argument has to be an expression"
     param_symbols = for param in *params.children
       assert param.type == 'sym', "function parameter declaration has to be a symbol"
-      param\quote scope, @registry
+      param\quote scope
 
-    body = body\quote scope, @registry
+    body = body\quote scope
     fn = FnDef param_symbols, body, scope
 
     scope\set name, Const.wrap fn
@@ -150,7 +150,7 @@ evaluates and continously updates expr1, expr2, ...
 the last expression's value is returned."
 
   eval: (scope, tail) =>
-    UpdateChildren [(expr\eval scope, @registry) or Const.empty! for expr in *tail]
+    UpdateChildren [(expr\eval scope) or Const.empty! for expr in *tail]
 
 class if_ extends Action
   @doc: "(if bool then-expr [else-xpr]) - make an eval-time const choice
@@ -165,13 +165,13 @@ to then-expr, otherwise it is equivalent to else-xpr if given, or nil otherwise.
 
     { xif, xthen, xelse } = tail
 
-    xif = L\push xif\eval, scope, @registry
+    xif = L\push xif\eval, scope
     xif = xif\getc!
 
     if xif
-      xthen\eval scope, @registry
+      xthen\eval scope
     elseif xelse
-      xelse\eval scope, @registry
+      xelse\eval scope
 
 class trace extends Action
   @doc: "(trace expr) - print an eval-time constant to the console"
@@ -180,7 +180,7 @@ class trace extends Action
     L\trace "evaling #{@}"
     assert #tail == 1, "'trace' takes exactly one parameter"
 
-    with val = L\push tail[1]\eval, scope, @registry
+    with val = L\push tail[1]\eval, scope
       L\print "trace:", val
 
 {
diff --git a/core/cell.moon b/core/cell.moon
index 65273d8..81409c3 100644
--- a/core/cell.moon
+++ b/core/cell.moon
@@ -1,6 +1,6 @@
 import Const from require 'core.const'
 import op_invoke, fn_invoke from require 'core.invoke'
-import Tag from require 'core.registry'
+import Tag from require 'core.tag'
 
 class Cell
 -- common
@@ -17,8 +17,8 @@ class Cell
   destroy: =>
 
 -- AST interface
-  eval: (scope, registry) =>
-    head = @head!\eval scope, registry
+  eval: (scope) =>
+    head = @head!\eval scope
     Action = switch head.type
       when 'opdef'
         -- scope\get 'op-invoke'
@@ -35,12 +35,11 @@ class Cell
           print head.__class.__name
         error "cannot evaluate expr with head #{head}"
 
-    @tag.registry = registry
     action = Action\get_or_create head, @tag
     action\eval scope, @tail!
 
-  quote: (scope, registry) =>
-    children = [child\quote scope, registry for child in *@children]
+  quote: (scope) =>
+    children = [child\quote scope for child in *@children]
     Cell @tag, children, @white
 
   clone: (parent) =>
diff --git a/core/init.moon b/core/init.moon
index c8f0265..f9a3b9e 100644
--- a/core/init.moon
+++ b/core/init.moon
@@ -22,24 +22,10 @@ globals = Scope.from_table require 'core.builtin'
   :globals
 
   parse: program\match
-  eval: do
-    class BuiltinRegistry
-      new: =>
-        @cnt = 1
-
-      init: (tag, expr) =>
-        tag\set @cnt
-        @cnt += 1
-
-      last: (index) =>
-      replace: (index, expr) =>
-
-    registry = BuiltinRegistry!
-
-    (str, inject) ->
+  eval: (str, inject) ->
       scope = Scope nil, globals
       scope\use inject if inject
 
       ast = assert (cell\match str), "failed to parse: #{str}"
-      Const.wrap ast\eval scope, registry
+      Const.wrap ast\eval scope
 }
diff --git a/core/invoke.moon b/core/invoke.moon
index 9c324e1..5ec4a82 100644
--- a/core/invoke.moon
+++ b/core/invoke.moon
@@ -29,7 +29,7 @@ class op_invoke extends Action
     
   eval: (scope, tail) =>
     L\trace "evaling #{@}"
-    args = L\push -> [L\push expr\eval, scope, @registry for expr in *tail]
+    args = L\push -> [L\push expr\eval, scope for expr in *tail]
 
     -- Const 'op', with @op
     with @op
@@ -58,15 +58,15 @@ class fn_invoke extends Action
     for i=1,#params
       name = params[i]\getc!
       argm = tail[i]
-      fn_scope\set name, L\push argm\eval, outer_scope, @registry
+      fn_scope\set name, L\push argm\eval, outer_scope
 
     body = body\clone @tag
 
-    body\eval fn_scope, @registry
+    body\eval fn_scope
 
 class do_expr extends Action
   eval: (scope, tail) =>
-    UpdateChildren [(expr\eval scope, @registry) or Const.empty! for expr in *tail]
+    UpdateChildren [(expr\eval scope) or Const.empty! for expr in *tail]
 
 {
   :op_invoke, :fn_invoke
diff --git a/core/parsing.moon b/core/parsing.moon
index c23b7b7..58dbf62 100644
--- a/core/parsing.moon
+++ b/core/parsing.moon
@@ -1,6 +1,6 @@
 import Const from require 'core.const'
 import Cell, RootCell from require 'core.cell'
-import Tag from require 'core.registry'
+import Tag from require 'core.tag'
 import R, S, P, V, C, Ct from require 'lpeg'
 
 -- whitespace
diff --git a/core/registry.moon b/core/registry.moon
index 7c89fa4..6afd361 100644
--- a/core/registry.moon
+++ b/core/registry.moon
@@ -1,75 +1,3 @@
-import Const from require 'core.const'
-import Scope from require 'core.scope'
-
-local ClonedTag
-
-class Tag
-  new: (@value) =>
-
-  clone: (parent) => ClonedTag @, parent
-
-  last: =>
-    if index = @index!
-      @registry\last index
-
-  keep: (expr) =>
-    index = assert @index!
-    assert expr == @registry\last index
-    @registry\replace index, expr
-
-  replace: (expr) =>
-    if index = @index!
-      @registry\replace index, expr
-    else
-      @registry\init @, expr
-
-index: => @value
-
-  set: (value) =>
-    assert not @value, "setting #{@} again"
-    @value = value
-
-  @blank: -> Tag!
-  @parse: (num) => @ tonumber num
-
-  stringify: => if @value then "[#{@value}]" else ''
-
-  __tostring: => if @value then "#{@value}" else '[blank]'
-
-class ClonedTag extends Tag
-  class DummyReg
-    destroy: =>
-
-  new: (@original, @parent) =>
-    @registry = @original.registry
-    @dummy = DummyReg!
-
-  keep: (expr) =>
-    super\keep expr
-    @original.registry or= @registry
-    @original\replace @dummy
-
-  replace: (expr) =>
-    super\replace expr
-    @original.registry or= @registry
-    @original\replace @dummy
-
-  index: =>
-    orig = @original\index!
-    parent = @parent\index!
-    if orig and parent
-      "#{parent}.#{orig}"
-
-  set: (value) => @original\set value
-
-  stringify: => error "cant stringify ClonedTag"
-
-  __tostring: =>
-    if @parent
-      "#{@parent}.#{@original}"
-    else
-      tostring @original
-
 class Registry
   new: () =>
     @map = {}
@@ -87,9 +15,20 @@ class Registry
     L\trace "reg: init pending to #{expr}"
     table.insert @pending, { :tag, :expr }
 
+  active: ->
+    assert Registry.active_registry, "no active Registry!"
+
 -- public methods
 
+  wrap: (fn) =>
+    (...) ->
+      @prepare!
+      with fn ...
+        @finalize!
+
   prepare: =>
+    assert not @prev, "already have a previous registry? #{@prev}"
+    @prev, @@active_registry = @@active_registry, @
     @last_map, @map, @pending = @map, {}, {}
 
   finalize: =>
@@ -106,9 +45,26 @@ class Registry
       tag\set @next_tag!
       @map[tag\index!] = expr
 
+    assert @ == @@active_registry, "not the active registry!"
+    @@active_registry, @prev = @prev, nil
+
   next_tag: => #@map + 1
 
+class SimpleRegistry extends Registry
+  new: =>
+    @cnt = 1
+
+  init: (tag, expr) =>
+    tag\set @cnt
+    @cnt += 1
+
+  last: (index) =>
+  replace: (index, expr) =>
+  finalize: =>
+    assert @ == @@active_registry, "not the active registry!"
+    @@active_registry, @prev = @prev, nil
+
 {
-  :Tag
   :Registry
+  :SimpleRegistry
 }
diff --git a/core/tag.moon b/core/tag.moon
new file mode 100644
index 0000000..47c43fa
--- /dev/null
+++ b/core/tag.moon
@@ -0,0 +1,71 @@
+import Registry from require 'core.registry'
+
+local ClonedTag
+
+class Tag
+  new: (@value) =>
+
+  clone: (parent) => ClonedTag @, parent
+
+  last: =>
+    if index = @index!
+      Registry.active!\last index
+
+  keep: (expr) =>
+    index = assert @index!
+    assert expr == Registry.active!\last index
+    Registry.active!\replace index, expr
+
+  replace: (expr) =>
+    if index = @index!
+      Registry.active!\replace index, expr
+    else
+      Registry.active!\init @, expr
+
+  index: => @value
+
+  set: (value) =>
+    assert not @value, "setting #{@} again"
+    @value = value
+
+  @blank: -> Tag!
+  @parse: (num) => @ tonumber num
+
+  stringify: => if @value then "[#{@value}]" else ''
+
+  __tostring: => if @value then "#{@value}" else '[blank]'
+
+class ClonedTag extends Tag
+  class DummyReg
+    destroy: =>
+
+  new: (@original, @parent) =>
+    @dummy = DummyReg!
+
+  keep: (expr) =>
+    super\keep expr
+    @original\replace @dummy
+
+  replace: (expr) =>
+    super\replace expr
+    @original\replace @dummy
+
+  index: =>
+    orig = @original\index!
+    parent = @parent\index!
+    if orig and parent
+      "#{parent}.#{orig}"
+
+  set: (value) => @original\set value
+
+  stringify: => error "cant stringify ClonedTag"
+
+  __tostring: =>
+    if @parent
+      "#{@parent}.#{@original}"
+    else
+      tostring @original
+
+{
+  :Tag
+}