merge Const and Stream into Value; Dataflow logic

lib not fully ported / functonial

24 files changed, 714 insertions, 585 deletions

diff --git a/copilot.moon b/copilot.moon
index 78848e5..a66c570 100644
--- a/copilot.moon
+++ b/copilot.moon
@@ -29,20 +29,21 @@ class Copilot
       return
 
     scope = Scope ast, globals
-    ok, err = pcall (@registry\wrap ast\eval), scope, @registry
+    ok, err = pcall ast\eval, scope, @registry
     if not ok
       L\error "error evaluating: #{err}"
       return
 
     @root = err
+    ast
 
-    spit @file, ast\stringify!
-
-  update: (dt) =>
+  tick: =>
     @poll!
 
     if @root
-      @root\update dt
+      ok, err = pcall @registry\wrap_tick @root\tick
+      if not ok
+        L\error err
 
   tb = (msg) -> debug.traceback msg, 2
   poll: =>
@@ -52,7 +53,8 @@ class Copilot
 
     if @last_modification < modification
       L\log "#{@file} changed at #{modification}"
-      L\push @\patch
+      ast = L\push @registry\wrap_eval @\patch
+      spit @file, ast\stringify!
       @last_modification = os.time!
 
 :Copilot
diff --git a/core/base.moon b/core/base.moon
index 1b1be5d..60ee460 100644
--- a/core/base.moon
+++ b/core/base.moon
@@ -1,21 +1,47 @@
 -- base definitions for extensions
+import Value from require 'core.value'
+
+unpack or= table.unpack
 
 -- a persistent expression Operator
 --
 -- accepts Const or Stream inputs and produces a Stream output
 class Op
-  update: (dt) =>
+  new: (type, init) =>
+    @impulses = {}
+
+    if type
+      @out = Value type, init
+
+  -- (re)-initialize this Op with the given inputs
+  -- after this method finishes, :tick(true) is called once, after which
+  -- @impulses and @out have to be set and may not change until :setup()
+  -- is called again.
+  setup: (@inputs) =>
 
-  -- set @out to a Value (Const or Stream)
-  setup: (...) =>
+  -- called once per frame if any inputs or impulses are dirty, and once
+  -- immediately after :setup(). 'first' will be true in the latter case.
+  -- Should update @out.
+  tick: (first) =>
 
+  -- called once when the Op is destroyed
   destroy: =>
 
+-- utilities
+  unwrap_inputs: =>
+    unpack [input! for input in *@inputs]
+
+  assert_types: (...) =>
+    num = select '#', ...
+    assert #@inputs >= num, "argument count mismatch"
+    for i = 1, num
+      expect = select i, ...
+      assert @inputs[i].type == expect, "expected argument #{i} of #{@} to be of type #{expect} but found #{@inputs[i]}"
+
 -- static
   __tostring: => "<op: #{@@__name}>"
   __inherited: (cls) => cls.__base.__tostring = @__tostring
 
-
 -- a builtin / special form / cell-evaluation strategy
 --
 -- responsible for quoting/evaluating subexpressions,
@@ -51,7 +77,7 @@ class Action
 -- static
   -- find & patch the action for the expression with Tag 'tag' if it exists,
   -- and is compatible with the new Cell contents, otherwise instantiate it.
-  -- register the action with the tag, evaluate it and return the ResultNode
+  -- register the action with the tag, evaluate it and return the Result
   @eval_cell: (scope, tag, head, tail) =>
     last = tag\last!
     compatible = last and
@@ -93,6 +119,7 @@ class FnDef
     "(fn (#{table.concat [p\stringify! for p in *@params], ' '}) ...)"
 
 {
+  :Dispatcher
   :Op
   :Action
   :FnDef
diff --git a/core/builtin.moon b/core/builtin.moon
index 71beac3..6abcbd9 100644
--- a/core/builtin.moon
+++ b/core/builtin.moon
@@ -1,6 +1,6 @@
 -- builtin special forms
 import Action, FnDef from require 'core.base'
-import ResultNode, Value, Const from require 'core.value'
+import Result, Value from require 'core.value'
 import Cell from require 'core.cell'
 import Scope from require 'core.scope'
 
@@ -13,7 +13,7 @@ prints the docstring for sym in the console"
     assert #tail == 1, "'doc' takes exactly one parameter"
 
     def = L\push tail[1]\eval, scope
-    with ResultNode children: { def }
+    with Result children: { def }
       def = def.value\const!\unwrap!
       L\print "(doc #{tail[1]\stringify!}):\n#{def.doc}\n"
 
@@ -35,9 +35,9 @@ updates all val-exprs."
         name = (name\quote scope)\unwrap 'sym'
 
         with val_expr\eval scope
-          scope\set name, .value
+          scope\set name, \make_ref!
 
-    ResultNode :children
+    Result :children
 
 class use extends Action
   @doc: "(use scope1 [scope2]...) - merge scopes into parent scope
@@ -49,10 +49,10 @@ all scopes have to be eval-time constants."
     L\trace "evaling #{@}"
     for child in *tail
       result = L\push child\eval, scope
-      value = result\value_only!\const!
+      value = result\const!
       scope\use value\unwrap 'scope', "'use' only works on scopes"
 
-    ResultNode!
+    Result!
 
 class require_ extends Action
   @doc: "(require name-str) - require a module
@@ -65,10 +65,10 @@ name-str has to be an eval-time constant."
     assert #tail == 1, "'require' takes exactly one parameter"
 
     result = L\push tail[1]\eval, scope
-    name = result\value_only!\const!
+    name = result\const!
 
     L\trace @, "loading module #{name}"
-    ResultNode value: Value.wrap require "lib.#{name\unwrap 'str'}"
+    Result value: Value.wrap require "lib.#{name\unwrap 'str'}"
 
 class import_ extends Action
   @doc: "(import sym1 [sym2]...) - require and define modules
@@ -81,9 +81,9 @@ requires modules sym1, sym2, ... and defines them as sym1, sym2, ... in the curr
 
     for child in *tail
       name = (child\quote scope)\unwrap 'sym'
-      scope\set name, Value.wrap require "lib.#{name}"
+      scope\set name, Result value: Value.wrap require "lib.#{name}"
 
-    ResultNode!
+    Result!
 
 class import_star extends Action
   @doc: "(import* sym1 [sym2]...) - require and use modules
@@ -99,7 +99,7 @@ requires modules sym1, sym2, ... and merges them into the current scope"
       name = (child\quote scope)\unwrap 'sym'
       scope\use (Value.wrap require "lib.#{name}")\unwrap 'scope'
 
-    ResultNode!
+    Result!
 
 class fn extends Action
   @doc: "(fn (p1 [p2]...) body-expr) - declare a (lambda) function
@@ -117,7 +117,7 @@ the symbols p1, p2, ... will resolve to the arguments passed to the function."
       param\quote scope
 
     body = body\quote scope
-    ResultNode value: Value.wrap FnDef param_symbols, body, scope
+    Result value: Value.wrap FnDef param_symbols, body, scope
 
 class defn extends Action
   @doc: "(defn name-sym (p1 [p2]...) body-expr) - define a function
@@ -138,8 +138,8 @@ declares a lambda (see (doc fn)) and defines it in the current scope"
     body = body\quote scope
     fn = FnDef param_symbols, body, scope
 
-    scope\set name, Value.wrap fn
-    ResultNode!
+    scope\set name, Result value: Value.wrap fn
+    Result!
 
 class do_expr extends Action
   @doc: "(do expr1 [expr2]...) - update multiple expressions
@@ -148,7 +148,7 @@ evaluates and continously updates expr1, expr2, ...
 the last expression's value is returned."
 
   eval: (scope, tail) =>
-    ResultNode children: [expr\eval scope for expr in *tail]
+    Result children: [expr\eval scope for expr in *tail]
 
 class if_ extends Action
   @doc: "(if bool then-expr [else-xpr]) - make an eval-time const choice
@@ -164,7 +164,7 @@ 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
-    xif = xif\value_only!\const!\unwrap!
+    xif = xif\const!\unwrap!
 
     if xif
       xthen\eval scope
@@ -189,8 +189,8 @@ class trace extends Action
   import: import_
   'import*': import_star
 
-  true: Const.bool true
-  false: Const.bool false
+  true: Value.bool true
+  false: Value.bool false
 
   :fn, :defn
   'do': do_expr
diff --git a/core/cell.moon b/core/cell.moon
index 642e1a6..0cb8e9f 100644
--- a/core/cell.moon
+++ b/core/cell.moon
@@ -1,5 +1,5 @@
 -- ALV Cell type
-import Const from require 'core.value'
+import Value from require 'core.value'
 import op_invoke, fn_invoke from require 'core.invoke'
 import Tag from require 'core.tag'
 
@@ -11,7 +11,8 @@ class Cell
   -- white:    optional sequence of whitespace segments ([0 .. #@children])
   new: (@tag=Tag.blank!, @children, @white) =>
     if not @white
-      @white = ['' for i=1,#@children+1]
+      @white = ['' for i=1,#@children]
+      @white[0] = ''
 
     assert #@white == #@children, "mismatched whitespace length"
 
@@ -22,8 +23,7 @@ class Cell
 
 -- AST interface
   eval: (scope) =>
-    head_result = @head!\eval scope
-    head = head_result.value\const!
+    head = (@head!\eval scope)\const!
     Action = switch head.type
       when 'opdef'
         -- scope\get 'op-invoke'
@@ -89,7 +89,7 @@ class Cell
 --
 -- evaluates with an implicit 'do' in the head
 class RootCell extends Cell
-  head: => Const.sym 'do'
+  head: => Value.sym 'do'
   tail: => @children
 
   stringify: =>
diff --git a/core/init.moon b/core/init.moon
index b885747..a309722 100644
--- a/core/init.moon
+++ b/core/init.moon
@@ -2,7 +2,7 @@ L or= setmetatable {}, __index: => ->
 
 import Op, Action, FnDef from require 'core.base'
 
-import Stream, Const, load_ from require 'core.value'
+import Value, Result, load_ from require 'core.value'
 import Scope from require 'core.scope'
 load_!
 
@@ -15,7 +15,7 @@ import cell, program from require 'core.parsing'
 globals = Scope.from_table require 'core.builtin'
 
 {
-  :Stream, :Const
+  :Value, :Result
   :Cell, :RootCell
   :Op, :Action, :FnDef
   :Scope
@@ -30,5 +30,5 @@ globals = Scope.from_table require 'core.builtin'
 
       ast = assert (cell\match str), "failed to parse: #{str}"
       result = ast\eval scope
-      result\value_only!
+      result\const!
 }
diff --git a/core/invoke.moon b/core/invoke.moon
index 5a6c420..a3932f8 100644
--- a/core/invoke.moon
+++ b/core/invoke.moon
@@ -1,4 +1,4 @@
-import ResultNode, Value from require 'core.value'
+import Result, Value from require 'core.value'
 import Action from require 'core.base'
 import Scope from require 'core.scope'
 
@@ -8,16 +8,17 @@ class op_invoke extends Action
 
     @op\destroy! if @op
 
-    def = head\const!\unwrap 'opdef', "cant op-invoke #{@head}"
+    def = head\unwrap 'opdef', "cant op-invoke #{@head}"
     @head, @op = head, def!
 
     true
     
   eval: (scope, tail) =>
     children = L\push -> [L\push expr\eval, scope for expr in *tail]
-    value = @op\setup unpack [child.value for child in *children]
+    @op\setup [child.value for child in *children]
+    @op\tick true
 
-    ResultNode :children, :value, op: @op
+    Result :children, value: @op.out, op: @op
 
 class fn_invoke extends Action
   -- @TODO:
@@ -32,7 +33,7 @@ class fn_invoke extends Action
     true
 
   eval: (outer_scope, tail) =>
-    { :params, :body, :scope } = @head\const!\unwrap 'fndef', "cant fn-invoke #{@head}"
+    { :params, :body, :scope } = @head\unwrap 'fndef', "cant fn-invoke #{@head}"
 
     assert #params == #tail, "argument count mismatch in #{@head}"
 
@@ -47,7 +48,7 @@ class fn_invoke extends Action
     result = body\eval fn_scope
 
     table.insert children, result
-    ResultNode :children, value: result.value
+    Result :children, value: result.value
 
 {
   :op_invoke, :fn_invoke
diff --git a/core/parsing.moon b/core/parsing.moon
index 96d8125..03ef85c 100644
--- a/core/parsing.moon
+++ b/core/parsing.moon
@@ -1,4 +1,4 @@
-import Const from require 'core.value'
+import Value from require 'core.value'
 import Cell, RootCell from require 'core.cell'
 import Tag from require 'core.tag'
 import R, S, P, V, C, Ct from require 'lpeg'
@@ -16,15 +16,15 @@ mspace = (comment + wc)^0 / 1            -- optional whitespace
 -- atoms
 digit = R '09'
 first = (R 'az', 'AZ') + S '-_+*/.!?='
-sym = first * (first + digit)^0 / Const\parse 'sym'
+sym = first * (first + digit)^0 / Value\parse 'sym'
 
-strd = '"' * (C ((P '\\"') + (P '\\\\') + (1 - P '"'))^0) * '"' / Const\parse 'str', '\"'
-strq = "'" * (C ((P "\\'") + (P '\\\\') + (1 - P "'"))^0) * "'" / Const\parse 'str', '\''
+strd = '"' * (C ((P '\\"') + (P '\\\\') + (1 - P '"'))^0) * '"' / Value\parse 'str', '\"'
+strq = "'" * (C ((P "\\'") + (P '\\\\') + (1 - P "'"))^0) * "'" / Value\parse 'str', '\''
 str = strd + strq
 
 int = digit^1
 float = (digit^1 * '.' * digit^0) + (digit^0 * '.' * digit^1)
-num = (float + int) / Const\parse 'num'
+num = (float + int) / Value\parse 'num'
 
 atom = num + sym + str
 
diff --git a/core/registry.moon b/core/registry.moon
index 4dd5bbb..e8272fa 100644
--- a/core/registry.moon
+++ b/core/registry.moon
@@ -1,7 +1,12 @@
+import Value from require 'core.value'
+
 class Registry
   new: () =>
     @map = {}
 
+    @tick = 0
+    @kr = Value.bool true
+
 -- methods for Tag
 
   last: (index) => @last_map[index]
@@ -15,37 +20,44 @@ class Registry
     L\trace "reg: init pending to #{expr}"
     table.insert @pending, { :tag, :expr }
 
-  active: ->
-    assert Registry.active_registry, "no active Registry!"
+  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, @
+  wrap_eval: (fn) => (...) ->
+    @grab!
     @last_map, @map, @pending = @map, {}, {}
 
-  finalize: =>
-    for tag, val in pairs @last_map
-      if not @map[tag]
-        val\destroy!
+    with fn ...
+      for tag, val in pairs @last_map
+        if not @map[tag]
+          val\destroy!
 
-    for { :tag, :expr } in *@pending
-      -- tag was solved by another pending registration
-      -- (e.g. first [A] is solved, then [5.A] is solved)
-      continue if tag\index!
+      for { :tag, :expr } in *@pending
+        -- tag was solved by another pending registration
+        -- (e.g. first [A] is solved, then [5.A] is solved)
+        continue if tag\index!
 
-      next_tag = @next_tag!
-      L\trace "assigned new tag #{next_tag} to #{tag} #{expr}"
-      tag\set next_tag
-      @map[tag\index!] = expr
+        next_tag = @next_tag!
+        L\trace "assigned new tag #{next_tag} to #{tag} #{expr}"
+        tag\set next_tag
+        @map[tag\index!] = expr
+
+      @release!
+
+  wrap_tick: (fn) => (...) ->
+    @grab!
+    @tick += 1
+    @kr\set true
+
+    with fn ...
+      @release!
+
+  grab: =>
+    assert not @prev, "already have a previous registry? #{@prev}"
+    @prev, @@active_registry = @@active_registry, @
 
+  release: =>
     assert @ == @@active_registry, "not the active registry!"
     @@active_registry, @prev = @prev, nil
 
diff --git a/core/scope.moon b/core/scope.moon
index aaa38f2..f795f97 100644
--- a/core/scope.moon
+++ b/core/scope.moon
@@ -1,12 +1,16 @@
-import Value from require 'core.value'
+import Result, Value from require 'core.value'
 
 class Scope
   new: (@node, @parent) =>
     @values = {}
 
-  set_raw: (key, val) => @values[key] = Value.wrap val, key
+  set_raw: (key, val) =>
+    value = Value.wrap val, key
+    @values[key] = Result :value
+
   set: (key, val) =>
     L\trace "setting #{key} = #{val} in #{@}"
+    assert val.__class == Result, "expected #{key}=#{val} to be Result"
     @values[key] = val
 
   get: (key, prefix='') =>
@@ -20,9 +24,9 @@ class Scope
     if not start
       return @parent and L\push -> @parent\get key
 
-    scope = @get start
-    assert scope and scope.type == 'scope', "cant find '#{prefix}#{start}' for '#{prefix}#{key}'"
-    scope\unwrap!\get rest, "#{prefix}#{start}/"
+    child = @get start
+    assert child and child.value.type == 'scope', "#{start} is not a scope (looking for #{key})"
+    child.value\unwrap!\get rest, "#{prefix}#{start}/"
 
   use: (other) =>
     L\trace "using defs from #{other} in #{@}"
@@ -31,7 +35,8 @@ class Scope
 
   from_table: (tbl) ->
     with Scope!
-      .values = { k, Value.wrap v, k for k,v in pairs tbl }
+      for k, v in pairs tbl
+        \set_raw k, v
 
   __tostring: =>
     buf = "<Scope"
diff --git a/core/value.moon b/core/value.moon
index f3f9796..986c846 100644
--- a/core/value.moon
+++ b/core/value.moon
@@ -1,9 +1,9 @@
 -- ALV Value types
-import Op, Action, FnDef from require 'core.base'
-
-local Scope
+local Scope, Registry, Op, Action, FnDef
 load_ = ->
   import Scope from require 'core.scope'
+  import Registry from require 'core.registry'
+  import Op, Action, FnDef from require 'core.base'
 
 ancestor = (klass) ->
   assert klass, "cant find the ancestor of nil"
@@ -16,26 +16,73 @@ ancestor = (klass) ->
 -- - a Value
 -- - an Op (to update)
 -- - children (results of subexpressions that were evaluated)
+-- - cached list of all Dispatchers affecting all Ops in the subtree
 --
--- ResultNodes form a tree that controls execution order and message passing
+-- Results form a tree that controls execution order and message passing
 -- between Ops.
-class ResultNode
+class Result
   -- params: table with optional keys op, value, children
   new: (params={}) =>
-    @op = params.op
     @value = params.value
+    @op = params.op
     @children = params.children or {}
 
-  -- unwrap value and assert that neither @op nor @children were set
-  value_only: (msg) =>
-    assert not @op and #@children == 0, msg or "pure expression expected"
+    @all_impulses = {}
+    for child in *@children
+      for d in pairs child.all_impulses
+        @all_impulses[d] = true
+
+    if @op
+      assert @op.impulses, "#{@op} not set up correctly (impulses)"
+      for d in *@op.impulses
+        @all_impulses[d] = true
+
+  -- asserts value-constness and returns the value
+  const: (msg) =>
+    assert not (next @all_impulses), msg or "eval-time const expected"
     @value
 
-  update: (dt) =>
+  -- create a value-copy of this result that has the same impulses but without
+  -- affecting the original's update logic
+  make_ref: =>
+    with Result value: @value
+      .all_impulses = @all_impulses
+
+  -- in depth-first order, tick all Ops who have dirty Stream inputs or impulses
+  --
+  -- short-circuits if there are no dirty Streams in the entire subtree
+  tick: =>
+    any_dirty = false
+    for stream in pairs @all_impulses
+      if stream\dirty!
+        any_dirty = true
+        break
+
+    -- early-out if no streams are dirty in this whole subtree
+    return unless any_dirty
+
     for child in *@children
-      child\update dt
-    @op\update dt if @op
+      child\tick!
+
+    if @op
+      -- we have to check self_dirty here, because streams from child
+      -- expressions might have changed
+      self_dirty = false
+      for stream in *@op.impulses
+        if stream\dirty!
+          self_dirty = true
+          break
+      for stream in *@op.inputs
+        if stream\dirty!
+          self_dirty = true
+          break
+
+      L\trace "#{op} is #{if self_dirty then 'dirty' else 'clean'}"
+      return unless self_dirty
+
+      @op\tick!
 
+-- static
   __tostring: =>
     buf = "<result=#{@value}"
     buf ..= " #{@op}" if @op
@@ -43,19 +90,18 @@ class ResultNode
     buf ..= ">"
     buf
 
-local Const, Stream
-
 -- ALV Type wrapper
 class Value
   -- @type      - type name.
   --              builtin types: * literals: sym, num, bool
   --                             * scope, opdef, fndef, builtin
   -- @value     - Lua value - access through :unwrap()
-  new: (@type, @value) =>
+  new: (@type, @value, @raw) =>
+    @updated = 0
 
-  -- asserts value-constness
-  -- returns self (for chaining)
-  const: => error 'not a constant'
+  dirty: => @updated == Registry.active!.tick
+
+  set: (@value) => @updated = Registry.active!.tick
 
   -- unwrap to the Lua type
   -- asserts @type == type, msg if given
@@ -63,14 +109,30 @@ class Value
     assert type == @type, msg or "#{@} is not a #{type}" if type
     @value
 
+-- AST interface
+  eval: (scope) =>
+    switch @type
+      when 'num', 'str'
+        Result value: @
+      when 'sym'
+        assert (scope\get @value), "undefined reference to symbol '#{@value}'"
+      else
+        error "cannot evaluate #{@}"
+
+  quote: => @
+
+  stringify: => assert @raw, "stringifying Value that wasn't parsed"
+
+  clone: (prefix) => @
+  -- in case of doubt:
+  -- clone: (prefix) => Value @type, @value, @raw
+
 -- static
   __tostring: =>
     value = if 'table' == (type @value) and rawget @value, '__base' then @value.__name else @value
     "<#{@@__name} #{@type}: #{value}>"
+  __call: (...) => @unwrap ...
   __eq: (other) => other.type == @type and other.value == @value
-  __inherited: (cls) =>
-    cls.__base.__tostring = @__tostring
-    cls.__base.__eq = @__eq
 
   -- wrap a Lua type
   @wrap: (val, name='(unknown)') ->
@@ -96,62 +158,26 @@ class Value
               error "#{name}: cannot wrap '#{val.__class.__name}' instance"
         else
           -- plain table
-          return Const 'scope', Scope.from_table val
+          return Value 'scope', Scope.from_table val
       else
         error "#{name}: cannot wrap Lua type '#{type val}'"
 
-    Const typ, val
-
-class Stream extends Value
-  new: (@type, @value=nil) =>
-
-  set: (@value) =>
-    -- set dirty flag (?)
-
-class Const extends Value
-  new: (type, value, @raw) =>
-    super type, value
-
--- Value interface
-  const: => @
-
--- AST interface
-  eval: (scope) =>
-    value = switch @type
-      when 'num', 'str'
-        @
-      when 'sym'
-        assert (scope\get @value), "undefined reference to symbol '#{@value}'"
-      else
-        error "cannot evaluate #{@}"
-
-    ResultNode :value
-
-  quote: => @
-
-  stringify: => @raw
+    Value typ, val
 
-  clone: (prefix) => @
-  -- in case of doubt:
-  -- clone: (prefix) => Const @type, @value, @raw
-
--- static
   unescape = (str) -> str\gsub '\\([\'"\\])', '%1'
-
   @parse: (type, sep) =>
     switch type
       when 'num' then (match) -> @ 'num', (tonumber match), match
       when 'sym' then (match) -> @ 'sym', match, match
       when 'str' then (match) -> @ 'str', (unescape match), sep .. match .. sep
 
-  @num: (num) -> Const 'num', num, tostring num
-  @str: (str) -> Const 'str', str, "'#{str}'"
-  @sym: (sym) -> Const 'sym', sym, sym
-  @bool: (bool) -> Const 'bool', bool, tostring bool
+  @num: (num) -> Value 'num', num, tostring num
+  @str: (str) -> Value 'str', str, "'#{str}'"
+  @sym: (sym) -> Value 'sym', sym, sym
+  @bool: (bool) -> Value 'bool', bool, tostring bool
 
 {
-  :ResultNode
+  :Result
   :Value
-  :Stream, :Const
   :load_
 }
diff --git a/init.moon b/init.moon
index d4f7e85..8bb80e6 100644
--- a/init.moon
+++ b/init.moon
@@ -1,7 +1,7 @@
 -- run from CLI
-import monotime, sleep from require 'system'
 import Logger from require 'logger'
 import Copilot from require 'copilot'
+import sleep from require 'system'
 
 arguments, key = {}
 for a in *arg
@@ -16,25 +16,8 @@ for a in *arg
 
 Logger.init arguments.log
 
-delta = do
-  period = 1 / 60
-  
-  local last
-  ->
-    if last
-      target, current = (last + period), monotime!
-      if current > target
-        L\warn 'Frame Skipped!'
-      else
-        sleep target - current
-
-    time = monotime!
-    with time - (last or time)
-      last = time
-
 copilot = Copilot arguments[1]
 
 while true
-  dt = delta!
-
-  copilot\update dt
+  copilot\tick!
+  sleep 1 / 1000
diff --git a/lib/debug.moon b/lib/debug.moon
index f642c2e..08a7f78 100644
--- a/lib/debug.moon
+++ b/lib/debug.moon
@@ -3,10 +3,13 @@ import Op from require 'core'
 class out extends Op
   @doc: "(out name-str value) - log value to the console"
 
-  setup: (@name, @value) =>
+  setup: (params) =>
+    super params
+    assert @inputs[2], "need a value"
+    @assert_types 'str', @inputs[2].type
 
-  update: (dt) =>
-    L\print "#{@name\unwrap 'str'}", @value\unwrap!
+  tick: =>
+    L\print @unwrap_inputs!
 
 {
   :out
diff --git a/lib/midi/core.moon b/lib/midi/core.moon
index 891de0a..7f661ed 100644
--- a/lib/midi/core.moon
+++ b/lib/midi/core.moon
@@ -1,5 +1,6 @@
 import RtMidiIn, RtMidiOut, RtMidi from require 'luartmidi'
 import band, bor, lshift, rshift from require 'bit32'
+import Op, Registry from require 'core'
 
 MIDI = {
   [0x9]: 'note-on'
@@ -15,75 +16,101 @@ MIDI = {
 
 rMIDI = {v,k for k,v in pairs MIDI}
 
-class Input
-  new: (name) =>
-    @input = RtMidiIn RtMidi.Api.UNIX_JACK
-
+find_port = (Klass, name) ->
+  with Klass RtMidi.Api.UNIX_JACK
     id = nil
-    for port=1,@input\getportcount!
-      if name == @input\getportname port
+    for port=1, \getportcount!
+      if name == \getportname port
         id = port
         break
 
-    @input\openport id
+    \openport id
+
+class MidiPort
+  new: (@inp, @out) =>
 
-    @listeners = {}
+  dirty: =>
+    @updated == Registry.active!.tick
 
   tick: =>
-    while true
-      delta, bytes = @input\getmessage!
-      break unless delta
-
-      { status, a, b } = bytes
-      chan = band status, 0xf
-      status = MIDI[rshift status, 4]
-      @dispatch status, chan, a, b
-
-  dispatch: (status, chan, a, b) =>
-    L\trace "dispatching MIDI event #{status} CH#{chan} #{a} #{b}"
-    for mask, handler in pairs @listeners
-      match = true
-      match and= status == mask.status if mask.status
-      match and= chan == mask.chan if mask.chan
-      match and= a == mask.a if mask.a
-      if match
-        handler status, chan, a, b
-
-  -- register a handler
-  -- mask is { :status, :chan, :a } (all keys optional)
-  -- returns mask for op convenience
-  attach: (mask, handler) =>
-    @listeners[mask] = handler
-    mask
-
-  detach: (mask) =>
-    @listeners[mask] = nil
-
-class Output
-  new: (name) =>
-    @output = RtMidiOut RtMidi.Api.UNIX_JACK
+    if @inp
+      @messages = while true
+        delta, bytes = @inp\getmessage!
+        break unless delta
+
+        { status, a, b } = bytes
+        chan = band status, 0xf
+        status = MIDI[rshift status, 4]
+        { :status, :chan, :a, :b }
+
+      if @messages
+        @updated = Registry.active!.tick
+
+  receive: =>
+    assert @inp, "#{@} is not an input port"
+    return unless @messages
+    coroutine.wrap ->
+      for msg in *@messages
+        coroutine.yield msg
 
-    id = nil
-    for port=1,@output\getportcount!
-      if name == @output\getportname port
-        id = port
-        break
+  send: (status, chan, a, b) =>
+    assert @out, "#{@} is not an output port"
+    if 'string' == type 'status'
+      status = bor (lshift rMIDI[status], 4), chan
+    @out\sendmessage status, a, b
 
-    @output\openport id
+class input extends Op
+  @doc: "(midi/input name) - create a MIDI input port"
 
-  send: (status, chan, a, b) =>
-    status = bor (lshift rMIDI[status], 4), chan
-    @output\sendmessage status, a, b
+  new: =>
+    super 'midi/port'
+    @impulses = { Registry.active!.kr }
+
+  setup: (params) =>
+    super params
+    @assert_types 'str'
+
+  tick: (first) =>
+    { name } = @inputs
+    if first or name\dirty!
+      @out\set MidiPort find_port RtMidiIn, name\unwrap!
+
+    @out\unwrap!\tick!
+
+class output extends Op
+  @doc: "(midi/output name) - create a MIDI output port"
+
+  new: =>
+    super 'midi/port'
+
+  setup: (params) =>
+    super params
+    @assert_types 'str'
+
+  tick: (first) =>
+    { name } = @inputs
+    if first or name\dirty!
+      @out\set MidiPort nil, find_port RtMidiOut, name\unwrap!
+
+class inout extends Op
+  @doc: "(midi/inout inname outname) - create a bidirectional MIDI port"
+
+  new: =>
+    super 'midi/port'
+    @impulses = { Registry.active!.kr }
+
+  setup: (params) =>
+    super params
+    @assert_types 'str', 'str'
+
+  tick: (first) =>
+    { inp, out } = @inputs
 
-class InOut
-  new: (inp, out) =>
-    @inp = Input inp
-    @out = Output out
+    if first or inp\dirty! or out\dirty!
+      inp, out = inp\unwrap!, out\unwrap!
+      @out\set MidiPort (find_port RtMidiIn, inp), (find_port RtMidiOut, out)
 
-  tick: (...) => @inp\tick ...
-  attach: (...) => @inp\attach ...
-  detach: (...) => @inp\detach ...
-  send: (...) => @out\send ...
+    @out\unwrap!\tick!
 
 apply_range = (range, val) ->
   if range.type == 'str'
@@ -100,8 +127,8 @@ apply_range = (range, val) ->
     error "range has to be a string or number"
 
 {
-  :Input
-  :Output
-  :InOut
+  :input
+  :output
+  :inout
   :apply_range
 }
diff --git a/lib/midi/init.moon b/lib/midi/init.moon
index c9e2476..03f5115 100644
--- a/lib/midi/init.moon
+++ b/lib/midi/init.moon
@@ -1,34 +1,31 @@
-import Stream, Const, Op from require 'core'
-import Input, apply_range from require 'lib.midi.core'
-
-dispatch = Input 'system:midi_capture_4'
+import Value, Op from require 'core'
+import input, output, inout, apply_range from require 'lib.midi.core'
 
 class gate extends Op
-  @doc: "(midi/gate note [chan]) - gate from note-on and note-off messages"
+  @doc: "(midi/gate port note [chan]) - gate from note-on and note-off messages"
 
-  destroy: =>
-    dispatch\detach @mask if @mask
-
-  setup: (note, chan) =>
-    dispatch\detach @mask if @mask
+  new: =>
+    super 'bool', false
 
-    note = note\const!\unwrap 'num'
-    chan = chan and chan\const!\unwrap 'num'
-    @value = false
+  setup: (params) =>
+    super params
+    @inputs[3] or= Value.num -1
+    @assert_types 'midi/port', 'num', 'num'
+    @impulses = { @inputs[1]\unwrap! }
 
-    @mask = dispatch\attach { :chan, a: note }, (status) ->
-      if status == 'note-on'
-        @out\set true
-      else if status == 'note-off'
-        @out\set false
+  tick: =>
+    local port, note, chan
+    { port, note, chan } = [i\unwrap! for i in *@inputs]
 
-    @out = Stream 'bool', false
-    @out
-
-  update: (dt) => dispatch\tick!
+    for msg in port\receive!
+      if msg.a == note and (chan == -1 or msg.chan == chan)
+        if msg.status == 'note-on'
+          @out\set true
+        elseif msg.status == 'note-off'
+          @out\set false
 
 class cc extends Op
-  @doc: "(midi/cc cc [chan [range]]) - MIDI CC to number
+  @doc: "(midi/cc port cc [chan [range]]) - MIDI CC to number
 
 range can be one of:
 - 'raw' [ 0 - 128[
@@ -37,24 +34,36 @@ range can be one of:
 - 'rad' [ 0 - tau[
 - (num) [ 0 - num["
 
-  destroy: =>
-    dispatch\detach @mask if @mask
+  new: =>
+    super 'num'
 
-  setup: (cc, chan, @range=Const.str'uni') =>
+  destroy: =>
     dispatch\detach @mask if @mask
 
-    cc = cc\const!\unwrap 'num'
-    chan = chan and chan\const!\unwrap 'num'
+  setup: (params) =>
+    super params
+    @inputs[3] or= Value.num -1
+    @inputs[4] or= Value.str 'uni'
+    @assert_types 'midi/port', 'num', 'num', 'str'
+    @impulses = { @inputs[1]\unwrap! }
 
-    @mask = dispatch\attach { status: 'control-change', :chan, a: cc }, (_, _, _, val) ->
-      @out\set apply_range @range, val
+    if not @out\unwrap!
+      @out\set apply_range @inputs[4], 0
 
-    @out = Stream 'num', 0
-    @out
+  tick: =>
+    local port, cc, chan
+    { port, cc, chan } = [i\unwrap! for i in *@inputs]
 
-  update: (dt) => dispatch\tick!
+    for msg in port\receive!
+      if msg.status == 'control-change' and
+         (chan == -1 or msg.chan == chan) and
+         msg.a == cc
+        @out\set apply_range @inputs[4], msg.b
 
 {
+  :input
+  :output
+  :inout
   :gate
   :cc
 }
diff --git a/lib/midi/launchctl.moon b/lib/midi/launchctl.moon
index 778a724..c0d5e24 100644
--- a/lib/midi/launchctl.moon
+++ b/lib/midi/launchctl.moon
@@ -1,13 +1,12 @@
-import Stream, Const, Op from require 'core'
-import InOut, apply_range from require 'lib.midi.core'
+import Value, Op from require 'core'
+import apply_range from require 'lib.midi.core'
 import bor, lshift from require 'bit32'
 
-launch = InOut 'system:midi_capture_4', 'system:midi_playback_4'
-
+unpack or= table.unpack
 color = (r, g) -> bor 12, r, (lshift g, 4)
 
 class cc_seq extends Op
-  @doc: "(launctl/cc-seq i start chan [steps [range]]) - CC-Sequencer
+  @doc: "(launctl/cc-seq port i start chan [steps [range]]) - CC-Sequencer
 
 returns the value for the i-th step steps (buttons starting from start).
 steps defaults to 8.
@@ -19,43 +18,41 @@ range can be one of:
 - 'rad' [ 0 - tau[
 - (num) [ 0 - num["
 
-  destroy: =>
-    launch\detach @mask if @mask
-
   new: =>
+    super 'num'
     @steps = {}
-    @out = Stream 'num'
 
-  setup: (@i, start, chan, steps=(Const.num 8), @range=Const.str 'uni') =>
-    launch\detach @mask if @mask
+  setup: (params) =>
+    super params
 
-    @start = start\const!\unwrap 'num'
-    @chan = chan\const!\unwrap 'num'
-    steps = steps\const!\unwrap 'num'
+    @inputs[5] or= Value.num 8
+    @inputs[6] or= Value.str 'uni'
+    @assert_types 'midi/port', 'num', 'num', 'num', 'num', 'str'
+    @impulses = { @inputs[1]\unwrap! }
 
-    while steps > #@steps
-      table.insert @steps, 0
-    while steps < #@steps
-      table.remove @steps
-
-    @mask = launch\attach { status: 'control-change', chan: @chan }, (_, _, cc, val) -> @change cc, val
-    @out
+    if not @out\unwrap!
+      @out\set apply_range @inputs[6], 0
 
-  change: (cc, val) =>
-    i = cc - @start
-    if i < #@steps
-      @steps[i+1] = val
+  tick: =>
+    port, i, start, chan, steps = unpack [i\unwrap! for i in *@inputs]
+    port = @inputs[1]\unwrap!
+    _, i, start, chan, steps = unpack @inputs
 
-  update: (dt) =>
-    launch\tick!
-
-    curr_i = (@i\unwrap 'num') % #@steps
+    curr_i = i\unwrap! % #@steps
+    changed = false
 
-    @out\set apply_range @range, @steps[curr_i+1]
+    for msg in port\receive!
+      if msg.status == 'control-change' and msg.chan == chan
+        i = msg.a - start
+        if i < #@steps
+          @steps[i+1] = msg.b
+          changed = i == curr_i
 
+    if changed or i\dirty! or start\dirty! or chan\dirty! or steps\diry!
+      @out\set apply_range @inputs[6], @steps[curr_i+1]
 
 class gate_seq extends Op
-  @doc: "(launctl/gate-seq i start chan [steps]) - Gate-Sequencer
+  @doc: "(launctl/gate-seq port i start chan [steps]) - Gate-Sequencer
 
 returns true or false for the i-th step steps (buttons starting from start).
 steps defaults to 8."
diff --git a/lib/osc.moon b/lib/osc.moon
index fed1697..3bac3f1 100644
--- a/lib/osc.moon
+++ b/lib/osc.moon
@@ -2,22 +2,39 @@ import Stream, Op from require 'core'
 import pack, unpack from require 'osc'
 import dns, udp from require 'socket'
 
+class addr extends Op
+  @doc: "(remote host port) - UDP remote definition"
+
+  new: =>
+    super 'udp/remote'
+    @@udp or= udp!
+
+  setup: (params) =>
+    super params
+    @assert_types 'str', 'num'
+
+  tick: =>
+    host, port = @unwrap_inputs!
+    ip = dns.toip host
+    @out\set { :ip, :port }
+
 class out extends Op
   @doc: "(out host port path val) - send a value via OSC"
 
   new: (...) =>
-    super ...
-
     @@udp or= udp!
 
-  setup: (@host, @port, @path, @value) =>
+  setup: (params) =>
+    super params
+    assert @inputs[3], "need a value"
+    @assert_types 'udp/remote', 'str', @inputs[3].type
 
   update: (dt) =>
-    ip = dns.toip @host\unwrap 'str'
-    port = @port\unwrap 'num'
-    msg = pack (@path\unwrap 'str'), @value\unwrap!
+    remote, path, value = @unwrap_inputs!
+    msg = pack path, value
     @@udp\sendto msg, ip, port
 
 {
+  :addr
   :out
 }
diff --git a/lib/time.moon b/lib/time.moon
index 7ce8b84..c49a7d7 100644
--- a/lib/time.moon
+++ b/lib/time.moon
@@ -1,7 +1,31 @@
-import Stream, Const, Op from require 'core'
+import Registry, Value, Op from require 'core'
+import monotime from require 'system'
+
+delta = do
+  period = 1 / 60
+  
+  local last
+  ->
+
+class clock extends Op
+  new: =>
+    super 'num'
+    @impulses = { Registry.active!.kr }
+    @out\set 0
+
+  setup: (params) =>
+    super params
+    @last = monotime!
+
+  tick: =>
+    time = monotime!
+    dt = time - @last
+    if dt >= 1/60
+      @out\set dt
+      @last = time
 
 class lfo extends Op
-  @doc: "(lfo freq [wave]) - low-frequency oscillator
+  @doc: "(lfo clock freq [wave]) - low-frequency oscillator
 
 oscillates between 0 and 1 at the frequency freq.
 wave selects the wave shape from the following (default sin):
@@ -10,89 +34,96 @@ wave selects the wave shape from the following (default sin):
 - tri"
 
   tau = math.pi * 2
-  new: (...) =>
-    super ...
-    print "creating LFO"
-    @out = Stream 'num'
+  new: =>
+    super 'num'
     @phase = 0
 
-  default_wave = Const 'str', 'sin'
-  setup: (@freq, @wave=default_wave) =>
-    assert @freq, "lfo requires a frequency value"
-    L\trace "setup #{@}, freq=#{@freq}, wave=#{@wave}"
-    @out
+  default_wave = Value.str 'sin'
+  setup: (params) =>
+    super params
 
-  update: (dt) =>
-    @phase += dt * @freq\unwrap 'num'
-    @out\set switch @wave\unwrap!
-      when 'sin' then .5 + .5 * math.cos @phase * tau
-      when 'saw' then @phase % 1
-      when 'tri' then math.abs (2*@phase % 2) - 1
-      else error "unknown wave type"
+    @inputs[3] or= default_wave
+    @assert_types 'num', 'num', 'str'
+
+  tick: =>
+    -- if clock is dirty
+    if @inputs[1].dirty
+      dt, freq, wave = @unwrap_inputs!
+      @phase += dt * freq
+      @out\set switch wave
+        when 'sin' then .5 + .5 * math.cos @phase * tau
+        when 'saw' then @phase % 1
+        when 'tri' then math.abs (2*@phase % 2) - 1
+        else error "unknown wave type"
 
 class ramp extends Op
-  @doc: "(ramp period [max]) - sawtooth lfo
+  @doc: "(ramp clock period [max]) - sawtooth lfo
 
-ramps from 0 to max (default same as ramp) once every period seconds"
+ramps from 0 to max (default same as ramp) once every period seconds."
 
-  new: (...) =>
-    super ...
-    @out = Stream 'num'
+  new: =>
+    super 'num'
     @phase = 0
-    @out
 
-  setup: (@period, @max) =>
-    assert @period, "tick requires a period value"
+  setup: (params) =>
+    super params
+    assert @inputs[1].type == 'num', "tick requires a clock value"
+    assert @inputs[2].type == 'num', "tick requires a period value"
 
-  update: (dt) =>
-    period = @period\unwrap 'num'
-    max = if @max then @max\unwrap! else period
-    @phase += dt / period
+  tick: =>
+    -- if clock is dirty
+    if @inputs[1].dirty
+      dt, period, max = @unwrap_inputs!
+      max or= period
+      @phase += dt / period
 
-    if @phase >= 1
-      @phase -= 1
+      if @phase >= 1
+        @phase -= 1
 
-    @out\set @phase * max
+      @out\set @phase * max
 
 class tick extends Op
-  @doc: "(tick period) - count ticks
+  @doc: "(tick clock period) - count ticks
 
 counts upwards by one every period seconds and returns the number of completed ticks."
-  new: (...) =>
-    super ...
-    @out = Stream 'num'
+  new: =>
+    super 'num'
     @phase = 0
 
-  setup: (@period) =>
-    assert @period, "tick requires a period value"
-    @out
+  setup: (params) =>
+    @assert_types 'num', 'num'
 
   update: (dt) =>
-    @phase += dt / @period\unwrap 'num'
-    @out\set math.floor @phase
+    -- if clock is dirty
+    if @inputs[1].dirty
+      dt, period = @unwrap_inputs!
+      @phase += dt / period
+
+      @out\set math.floor @phase
 
 class every extends Op
-  @doc: "(every period) - sometimes true
+  @doc: "(every clock period) - trigger every period seconds
 
 returns true once every period seconds."
-  new: (...) =>
-    super ...
-    @out = Stream 'bool'
+  new: =>
+    super 'bang'
     @phase = 0
 
   setup: (@period) =>
-    assert @period, "every requires a period value"
-    @out
+    @assert_types 'num', 'num'
 
   update: (dt) =>
-    @phase += dt / @period\unwrap 'num'
-    if @phase > 1
-      @phase -= 1
-      @out\set true
-    else
-      @out\set false
+    -- if clock is dirty
+    if @inputs[1].dirty
+      dt, period = @unwrap_inputs!
+      @phase += dt / period
+
+      if @phase >= 1
+        @phase -= 1
+        @out\set true
 
 {
+  :clock
   :lfo
   :ramp
   :tick
diff --git a/lib/util.moon b/lib/util.moon
index 192c489..04d012f 100644
--- a/lib/util.moon
+++ b/lib/util.moon
@@ -1,4 +1,4 @@
-import Stream, Const, Op from require 'core'
+import Op from require 'core'
 
 class switch_ extends Op
   @doc: "(switch i v0 [v1 v2...]) - switch between multiple inputs
@@ -7,85 +7,91 @@ when i is true, the first value is reproduced.
 when i is false, the second value is reproduced.
 when i is a num, it is (floor)ed and the matching argument (starting from 0) is reproduced."
 
-  setup: (@i, ...) =>
-    @choices = { ... }
+  setup: (params) =>
+    super params
 
-    typ = @choices[1].type
-    for inp in *@choices[2,]
-      assert inp.type == typ, "not all values have the same type: #{typ} != #{inp.type}"
+    { i, first } = @inputs
+    assert i.type == 'bool' or i.type == 'num', "#{@}: i has to be bool or num"
 
-    @out = Stream typ
-    @out
+    for inp in *@inputs[3,]
+      assert inp.type == first.type, "not all values have the same type: #{first.type} != #{inp.type}"
+    @out = Stream first.type
 
   update: (dt) =>
-    i = @i\unwrap!
+    i = @inputs[1]\unwrap!
     active = switch i
       when true
-        @choices[1]
+        @inputs[2]
       when false
-        @choices[2]
+        @inputs[3]
       else
-        i = 1 + (math.floor i) % #@choices
-        @choices[i]
+        i = 2 + (math.floor i) % (#@inputs - 1)
+        @inputs[i]
     @out\set active and active\unwrap!
 
-class switch_pause extends Op
-  @doc: "(switch- i v0 [v1 v2...]) - switch and pause multiple inputs
+--class switch_pause extends Op
+--  @doc: "(switch- i v0 [v1 v2...]) - switch and pause multiple inputs
+--
+--like (switch ...) except that the unused inputs are paused."
+--
+--  setup: (@i, ...) =>
+--    @choices = { ... }
+--
+--    typ = @choices[1].type
+--    for inp in *@choices[2,]
+--      assert inp.type == typ, "not all values have the same type: #{typ} != #{inp.type}"
+--
+--    @out = Stream typ
+--    @out
+--
+--  update: (dt) =>
+--    i = @i\unwrap!
+--    active = switch i
+--      when true
+--        @choices[1]
+--      when false
+--        @choices[2]
+--      else
+--        i = 1 + (math.floor i) % #@choices
+--        @choices[i]
+--
+--    @out\set if active
+--      active\unwrap!
 
-like (switch ...) except that the unused inputs are paused."
-
-  setup: (@i, ...) =>
-    @choices = { ... }
-
-    typ = @choices[1].type
-    for inp in *@choices[2,]
-      assert inp.type == typ, "not all values have the same type: #{typ} != #{inp.type}"
-
-    @out = Stream typ
-    @out
-
-  update: (dt) =>
-    i = @i\unwrap!
-    active = switch i
-      when true
-        @choices[1]
-      when false
-        @choices[2]
-      else
-        i = 1 + (math.floor i) % #@choices
-        @choices[i]
+class edge extends Op
+  @doc: "(edge bool) - convert rising edges to bangs"
 
-    @out\set if active
-      active\unwrap!
+  new: =>
+    super 'bang'
 
-class edge extends Op
-  setup: (@i) =>
-    @last = false
-    @out = Stream @i.type
-    @out
+  setup: (params) =>
+    super params
+    @assert_types 'bool'
 
   update: (dt) =>
-    now = @i\unwrap!
-    @out\set not @last and now
-    @last = now
+    now = @params[1]\unwrap!
+    if now and not @last
+      @out\set true
+      @last = now
 
 class keep extends Op
-  @doc: "(keep value [default]) - keep the last non-nil value
+  @doc: "(keep value [init]) - keep the last non-nil value
 
 always reproduces the last non-nil value the input produced or default.
 default defaults to zero."
 
-  setup: (@i, @default=Const.num 0) =>
-    @out = Stream @i.type, @default.value
-    @out
+  setup: (params) =>
+    super params
+    { i, init } = @inputs
+    @out = Value i.type, default and init\unwrap!
 
-  update: (dt) =>
-    if next = @i\unwrap!
+  tick =>
+    if next = @params[1]\unwrap!
       @out\set next
 
 {
   'switch': switch_
-  'switch-': switch_pause
+--  'switch-': switch_pause
   :edge
   :keep
 }
diff --git a/spec/cell_spec.moon b/spec/cell_spec.moon
index b31ef99..fcf9861 100644
--- a/spec/cell_spec.moon
+++ b/spec/cell_spec.moon
@@ -1,31 +1,31 @@
-import Cell, RootCell, Const, Scope, globals from require 'core'
+import Cell, RootCell, Value, Scope, globals from require 'core'
 import Registry from require 'core.registry'
 import Logger from require 'logger'
 Logger.init 'silent'
 
-hello_world = Cell nil, { (Const.sym 'hello'), (Const.str 'world') }
-two_plus_two = Cell nil, { (Const.sym '+'), (Const.num 2), (Const.num 2) }
+hello_world = Cell nil, { (Value.sym 'hello'), (Value.str 'world') }
+two_plus_two = Cell nil, { (Value.sym '+'), (Value.num 2), (Value.num 2) }
 
 describe 'Cell', ->
   it 'supports quoting', ->
     with hello_world\quote!
       assert.is.equal Cell, .__class
-      assert.is.equal (Const.sym 'hello'), \head!
-      assert.is.same { Const.str 'world' }, \tail!
+      assert.is.equal (Value.sym 'hello'), \head!
+      assert.is.same { Value.str 'world' }, \tail!
 
     with two_plus_two\quote!
       assert.is.equal Cell, .__class
-      assert.is.equal (Const.sym '+'), \head!
-      assert.is.same { (Const.num 2), (Const.num 2) }, \tail!
+      assert.is.equal (Value.sym '+'), \head!
+      assert.is.same { (Value.num 2), (Value.num 2) }, \tail!
 
 
 describe 'RootCell', ->
   test 'head is always "do"', ->
     cell = RootCell\parse {}
-    assert.is.equal (Const.sym 'do'), cell\head!
+    assert.is.equal (Value.sym 'do'), cell\head!
 
     cell = RootCell nil, { hello_world, two_plus_two }
-    assert.is.equal (Const.sym 'do'), cell\head!
+    assert.is.equal (Value.sym 'do'), cell\head!
 
   test 'tail is all children', ->
     cell = RootCell\parse {}
diff --git a/spec/const_spec.moon b/spec/const_spec.moon
deleted file mode 100644
index 4def3a6..0000000
--- a/spec/const_spec.moon
+++ /dev/null
@@ -1,122 +0,0 @@
-import Const, Op, Action, Scope from require 'core'
-import Logger from require 'logger'
-Logger.init 'silent'
-
-class TestOp extends Op
-  new: (...) => super ...
-
-class TestAction extends Action
-  new: (...) =>
-
-describe 'Const', ->
-  describe 'wraps', ->
-    test 'numbers', ->
-      got = Const.wrap 3
-      assert.is.equal 'num', got.type
-      assert.is.equal 3, got.value
-
-    test 'strings', ->
-      got = Const.wrap "im a happy string"
-      assert.is.equal 'str', got.type
-      assert.is.equal "im a happy string", got.value
-
-    test 'Consts', ->
-      pi = Const 'num', 3.14
-      got = Const.wrap pi
-
-      assert.is.equal pi, got
-
-    test 'Opdefs', ->
-      got = Const.wrap TestOp
-
-      assert.is.equal 'opdef', got.type
-      assert.is.equal TestOp, got.value
-
-    test 'Bultins', ->
-      got = Const.wrap TestAction
-
-      assert.is.equal 'builtin', got.type
-      assert.is.equal TestAction, got.value
-
-    test 'Scopes', ->
-      sub = Scope!
-      got = Const.wrap sub
-
-      assert.is.equal 'scope', got.type
-      assert.is.equal sub, got.value
-
-    test 'tables', ->
-      pi = Const 'num', 3.14
-      got = Const.wrap { :pi }
-
-      assert.is.equal 'scope', got.type
-      assert.is.equal pi, got.value\get 'pi'
-
-  describe 'unwraps', ->
-    test 'get!, getc!', ->
-      assert.is.equal 3.14, (Const.num 3.14)\getc!
-      assert.is.equal 'hi', (Const.str 'hi')\getc!
-      assert.is.equal 'hi', (Const.sym 'hi')\getc!
-
-      assert.is.equal 3.14, (Const.num 3.14)\get!
-      assert.is.equal 'hi', (Const.str 'hi')\get!
-      assert.is.equal 'hi', (Const.sym 'hi')\get!
-
-    test 'with type assert', ->
-      assert.is.equal 3.14, (Const.num 3.14)\getc 'num'
-      assert.is.equal 'hi', (Const.str 'hi')\getc 'str'
-      assert.is.equal 'hi', (Const.sym 'hi')\getc 'sym'
-      assert.has_error -> (Const.num 3.14)\getc 'sym'
-      assert.has_error -> (Const.str 'hi')\getc 'num'
-      assert.has_error -> (Const.sym 'hi')\getc 'str'
-
-      assert.is.equal 3.14, (Const.num 3.14)\get 'num'
-      assert.is.equal 'hi', (Const.str 'hi')\get 'str'
-      assert.is.equal 'hi', (Const.sym 'hi')\get 'sym'
-      assert.has_error -> (Const.num 3.14)\get 'sym'
-      assert.has_error -> (Const.str 'hi')\get 'num'
-      assert.has_error -> (Const.sym 'hi')\get 'str'
-
-  describe 'checks equality', ->
-    test 'using the type', ->
-      val = Const 'num', 3
-      assert.is.equal (Const.num 3), val
-      assert.not.equal (Const.str '3'), val
-
-      val = Const 'str', 'hello'
-      assert.is.equal (Const.str 'hello'), val
-      assert.not.equal (Const.sym 'hello'), val
-
-    test 'using the value', ->
-      val = Const 'num', 3
-      assert.is.equal (Const.num 3), val
-      assert.not.equal (Const.num 4), val
-
-  describe 'evaluates literal', ->
-    test 'constants to themselves', ->
-      assert_noop = (val) -> assert.is.equal val, val\eval!
-
-      assert_noop Const.num 2
-      assert_noop Const.str 'hello'
-
-    test 'symbols in the scope', ->
-      scope = with Scope!
-        \set 'number', Const.num 3
-        \set 'hello', Const.str "world"
-        \set 'goodbye', Const.sym "again"
-
-      assert_eval = (sym, val) ->
-        const = Const.sym sym
-        assert.is.equal val, const\eval scope
-
-      assert_eval 'number', Const.num 3
-      assert_eval 'hello', Const.str "world"
-      assert_eval 'goodbye', Const.sym "again"
-
-  describe 'quotes literals', ->
-    test 'as themselves', ->
-      assert_noop = (val) -> assert.is.equal val, val\quote!
-
-      assert_noop Const.num 2
-      assert_noop Const.str 'hello'
-      assert_noop Const.sym 'world'
diff --git a/spec/parsing_spec.moon b/spec/parsing_spec.moon
index 2e7da7f..ddf760f 100644
--- a/spec/parsing_spec.moon
+++ b/spec/parsing_spec.moon
@@ -1,5 +1,5 @@
 import space, atom, expr, explist, cell, program, comment from require 'core.parsing'
-import Const from require 'core'
+import Value from require 'core'
 import Logger from require 'logger'
 Logger.init 'silent'
 
@@ -16,48 +16,48 @@ describe 'atom parsing', ->
   test 'symbols', ->
     sym = verify_parse_nope atom, 'some-toast nope'
     assert.is.equal 'sym', sym.type
-    assert.is.equal 'some-toast', sym\getc!
+    assert.is.equal 'some-toast', sym\unwrap!
     assert.is.equal 'some-toast', sym\stringify!
 
   describe 'numbers', ->
     it 'parses ints', ->
       num = verify_parse_nope atom, '1234 nope'
       assert.is.equal 'num', num.type
-      assert.is.equal 1234, num\getc!
+      assert.is.equal 1234, num\unwrap!
       assert.is.equal '1234', num\stringify!
 
     it 'parses floats', ->
       num = verify_parse_nope atom, '0.123 nope'
       assert.is.equal 'num', num.type
-      assert.is.equal 0.123, num\getc!
+      assert.is.equal 0.123, num\unwrap!
 
       num = verify_parse_nope atom, '.123 nope'
       assert.is.equal 'num', num.type
-      assert.is.equal 0.123, num\getc!
+      assert.is.equal 0.123, num\unwrap!
 
       num = verify_parse_nope atom, '0. nope'
       assert.is.equal 'num', num.type
-      assert.is.equal 0, num\getc!
+      assert.is.equal 0, num\unwrap!
 
   describe 'strings', ->
     it 'parses double-quote strings', ->
       str = verify_parse_nope atom, '"help some stuff!" nope'
       assert.is.equal 'str', str.type
-      assert.is.equal 'help some stuff!', str\getc!
+      assert.is.equal 'help some stuff!', str\unwrap!
 
     it 'parses single-quote strings', ->
       str = verify_parse_nope atom, "'help some stuff!' nope"
       assert.is.equal 'str', str.type
-      assert.is.equal "help some stuff!", str\getc!
+      assert.is.equal "help some stuff!", str\unwrap!
 
     it 'handles escapes', ->
       str = verify_parse_nope atom, '"string with \\"quote\\"s and \\\\" nope'
       assert.is.equal 'str', str.type
-      assert.is.equal 'string with \"quote\"s and \\', str\getc!
+      assert.is.equal 'string with \"quote\"s and \\', str\unwrap!
 
       str = verify_parse_nope atom, "'string with \\'quote\\'s and \\\\' nope"
       assert.is.equal 'str', str.type
-      assert.is.equal "string with \'quote\'s and \\", str\getc!
+      assert.is.equal "string with \'quote\'s and \\", str\unwrap!
 
 describe 'Cell', ->
   test 'basic parsing', ->
@@ -65,9 +65,9 @@ describe 'Cell', ->
                                 "friend" )'
 
     assert.is.equal 3, #node.children
-    assert.is.equal (Const.num 3), node.children[1]
-    assert.is.equal (Const.sym 'ok-yes'), node.children[2]
-    assert.is.equal (Const.str 'friend'), node.children[3]
+    assert.is.equal (Value.num 3), node.children[1]
+    assert.is.equal (Value.sym 'ok-yes'), node.children[2]
+    assert.is.equal (Value.str 'friend'), node.children[3]
 
   test 'tag parsing', ->
     node = verify_parse cell, '([42]tagged 2)'
@@ -88,8 +88,8 @@ describe 'RootCell parsing', ->
       node = verify_parse program, str
 
       assert.is.equal 2, #node.children
-      assert.is.equal (Const.num 3), node.children[1]
-      assert.is.equal (Const.sym 'ok-yes'), node.children[2]
+      assert.is.equal (Value.num 3), node.children[1]
+      assert.is.equal (Value.sym 'ok-yes'), node.children[2]
 
     it 'at the front of the string', ->
       verify ' 3\tok-yes'
diff --git a/spec/scope_spec.moon b/spec/scope_spec.moon
index 9e7ab80..471bbce 100644
--- a/spec/scope_spec.moon
+++ b/spec/scope_spec.moon
@@ -1,4 +1,4 @@
-import Scope, Const, Op from require 'core'
+import Scope, Value, Op from require 'core'
 import Logger from require 'logger'
 Logger.init 'silent'
 
@@ -12,27 +12,27 @@ describe 'Scope', ->
     test 'numbers', ->
       scope\set_raw 'num', 3
 
-      got = scope\get 'num'
+      got = (scope\get 'num')\const!
       assert.is.equal 'num', got.type
       assert.is.equal 3, got.value
 
     test 'strings', ->
       scope\set_raw 'str', "im a happy string"
 
-      got = scope\get 'str'
+      got = (scope\get 'str')\const!
       assert.is.equal 'str', got.type
       assert.is.equal "im a happy string", got.value
 
-    test 'Consts', ->
-      pi = Const 'num', 3.14
+    test 'Values', ->
+      pi = Value 'num', 3.14
       scope\set_raw 'pi', pi
 
-      assert.is.equal pi, scope\get 'pi'
+      assert.is.equal pi, (scope\get 'pi')\const!
 
     test 'Opdefs', ->
       scope\set_raw 'test', TestOp
 
-      got = scope\get 'test'
+      got = (scope\get 'test')\const!
       assert.is.equal 'opdef', got.type
       assert.is.equal TestOp, got.value
 
@@ -40,22 +40,22 @@ describe 'Scope', ->
       sub = Scope!
       scope\set_raw 'sub', sub
 
-      got = scope\get 'sub'
+      got = (scope\get 'sub')\const!
       assert.is.equal 'scope', got.type
       assert.is.equal sub, got.value
 
     test 'tables', ->
-      pi = Const 'num', 3.14
+      pi = Value 'num', 3.14
       scope\set_raw 'math',  { :pi }
 
-      got = scope\get 'math'
+      got = (scope\get 'math')\const!
       assert.is.equal 'scope', got.type
       assert.is.equal Scope, got.value.__class
-      assert.is.equal pi, got.value\get 'pi'
-      assert.is.equal pi, scope\get 'math/pi'
+      assert.is.equal pi, (got.value\get 'pi')\const!
+      assert.is.equal pi, (scope\get 'math/pi')\const!
 
-  it 'constifies in from_table', ->
-    pi = Const 'num', 3.14
+  it 'wraps Values in from_table', ->
+    pi = Value 'num', 3.14
     scope = Scope.from_table {
       num: 3
       str: "im a happy string"
@@ -64,35 +64,35 @@ describe 'Scope', ->
       test: TestOp
     }
 
-    got = scope\get 'num'
+    got = (scope\get 'num')\const!
     assert.is.equal 'num', got.type
     assert.is.equal 3, got.value
 
-    got = scope\get 'str'
+    got = (scope\get 'str')\const!
     assert.is.equal 'str', got.type
     assert.is.equal "im a happy string", got.value
 
-    assert.is.equal pi, scope\get 'pi'
+    assert.is.equal pi, (scope\get 'pi')\const!
 
-    got = scope\get 'test'
+    got = (scope\get 'test')\const!
     assert.is.equal 'opdef', got.type
     assert.is.equal TestOp, got.value
 
-    got = scope\get 'math'
+    got = (scope\get 'math')\const!
     assert.is.equal 'scope', got.type
-    assert.is.equal pi, scope\get 'math/pi'
+    assert.is.equal pi, (scope\get 'math/pi')\const!
 
   it 'gets from nested scopes', ->
     root = Scope!
     a = Scope!
     b = Scope!
 
-    pi = Const 'num', 3.14
+    pi = Value 'num', 3.14
     b\set_raw 'test', pi
     a\set_raw 'child', b
     root\set_raw 'deep', a
 
-    assert.is.equal pi, root\get 'deep/child/test'
+    assert.is.equal pi, (root\get 'deep/child/test')\const!
 
   describe 'inheritance', ->
     root = Scope!
@@ -102,13 +102,13 @@ describe 'Scope', ->
     scope = Scope nil, root
 
     it 'allows access', ->
-      got = scope\get 'inherited'
+      got = (scope\get 'inherited')\const!
       assert.is.equal 'str', got.type
       assert.is.equal "inherited string", got.value
 
     it 'can keep defs', ->
       scope\set_raw 'hidden', "overwritten"
 
-      got = scope\get 'hidden'
+      got = (scope\get 'hidden')\const!
       assert.is.equal 'str', got.type
       assert.is.equal "overwritten", got.value
diff --git a/spec/value_spec.moon b/spec/value_spec.moon
new file mode 100644
index 0000000..bc68c5b
--- /dev/null
+++ b/spec/value_spec.moon
@@ -0,0 +1,112 @@
+import Value, Result, Op, Action, Scope from require 'core'
+import Logger from require 'logger'
+Logger.init 'silent'
+
+class TestOp extends Op
+  new: (...) => super ...
+
+class TestAction extends Action
+  new: (...) =>
+
+describe 'Value', ->
+  describe 'wraps', ->
+    test 'numbers', ->
+      got = Value.wrap 3
+      assert.is.equal 'num', got.type
+      assert.is.equal 3, got.value
+
+    test 'strings', ->
+      got = Value.wrap "im a happy string"
+      assert.is.equal 'str', got.type
+      assert.is.equal "im a happy string", got.value
+
+    test 'Values', ->
+      pi = Value 'num', 3.14
+      got = Value.wrap pi
+
+      assert.is.equal pi, got
+
+    test 'Opdefs', ->
+      got = Value.wrap TestOp
+
+      assert.is.equal 'opdef', got.type
+      assert.is.equal TestOp, got.value
+
+    test 'Bultins', ->
+      got = Value.wrap TestAction
+
+      assert.is.equal 'builtin', got.type
+      assert.is.equal TestAction, got.value
+
+    test 'Scopes', ->
+      sub = Scope!
+      got = Value.wrap sub
+
+      assert.is.equal 'scope', got.type
+      assert.is.equal sub, got.value
+
+    test 'tables', ->
+      pi = Value 'num', 3.14
+      got = Value.wrap { :pi }
+
+      assert.is.equal 'scope', got.type
+      assert.is.equal pi, (got.value\get 'pi')\const!
+
+  describe 'unwraps', ->
+    test 'unwrap!', ->
+      assert.is.equal 3.14, (Value.num 3.14)\unwrap!
+      assert.is.equal 'hi', (Value.str 'hi')\unwrap!
+      assert.is.equal 'hi', (Value.sym 'hi')\unwrap!
+
+    test 'with type assert', ->
+      assert.is.equal 3.14, (Value.num 3.14)\unwrap 'num'
+      assert.is.equal 'hi', (Value.str 'hi')\unwrap 'str'
+      assert.is.equal 'hi', (Value.sym 'hi')\unwrap 'sym'
+      assert.has_error -> (Value.num 3.14)\unwrap 'sym'
+      assert.has_error -> (Value.str 'hi')\unwrap 'num'
+      assert.has_error -> (Value.sym 'hi')\unwrap 'str'
+
+  describe 'checks equality', ->
+    test 'using the type', ->
+      val = Value 'num', 3
+      assert.is.equal (Value.num 3), val
+      assert.not.equal (Value.str '3'), val
+
+      val = Value 'str', 'hello'
+      assert.is.equal (Value.str 'hello'), val
+      assert.not.equal (Value.sym 'hello'), val
+
+    test 'using the value', ->
+      val = Value 'num', 3
+      assert.is.equal (Value.num 3), val
+      assert.not.equal (Value.num 4), val
+
+  describe 'evaluates literal', ->
+    test 'numbers to consts', ->
+      assert_noop = (val) ->
+        assert.is.equal val, val\eval!\const!
+
+      assert_noop Value.num 2
+      assert_noop Value.str 'hello'
+
+    test 'symbols in the scope', ->
+      scope = with Scope!
+        \set 'number', Result value: Value.num 3
+        \set 'hello', Result value: Value.str "world"
+        \set 'goodbye', Result value: Value.sym "again"
+
+      assert_eval = (sym, val) ->
+        const = Value.sym sym
+        assert.is.equal val, (const\eval scope)\const!
+
+      assert_eval 'number', Value.num 3
+      assert_eval 'hello', Value.str "world"
+      assert_eval 'goodbye', Value.sym "again"
+
+  describe 'quotes literals', ->
+    test 'as themselves', ->
+      assert_noop = (val) -> assert.is.equal val, val\quote!
+
+      assert_noop Value.num 2
+      assert_noop Value.str 'hello'
+      assert_noop Value.sym 'world'
diff --git a/test.alv b/test.alv
index 7d51b9b..221b7ea 100644
--- a/test.alv
+++ b/test.alv
@@ -1,16 +1,9 @@
-([1]import* math time string util)
-([2]import osc envelope midi)
+([1]import* debug time)
+([2]import midi)
 
-([3]defn make-lfo (type)
-  ([8]fn ([5]f) ([7]lfo ([6]* f 0.5) type)))
+([3]trace "help")
 
-([9]def sin-lfo ([10]make-lfo 'sin'))
+([4]def device ([5]midi/input "system:midi_capture_2"))
 
-([11]defn send (name value)
-  ([13]osc/out '127.0.0.1' 9000
-    ([12].. '/param/' name '/set')
-    value))
-
-([23]send 'radius' ([25]([24]envelope/ar ([14]midi/cc 0) ([15]midi/cc 1)) ([27]midi/gate 36)))
-
-([19]send 'offset' ([20]sin-lfo ([16]keep ([26]midi/cc 24 0 4))))
+([6]out 'name' ([7]midi/cc device 0))
+([8]out 'gate' ([9]midi/gate device 44))