envelopes

4 files changed, 83 insertions, 2 deletions

diff --git a/core/const.moon b/core/const.moon
index b356f49..45c44eb 100644
--- a/core/const.moon
+++ b/core/const.moon
@@ -15,6 +15,7 @@ class Const
     sym: true
     str: true
     num: true
+    bool: true
     scope: true
     op: true
     opdef: true
@@ -53,7 +54,9 @@ class Const
 
   stringify: => @raw
 
-  clone: (prefix) => Const @type, @value, @raw
+  clone: (prefix) => @
+  -- in case of doubt:
+  -- clone: (prefix) => Const @type, @value, @raw
 
 -- static
   __tostring: =>
@@ -74,6 +77,7 @@ class Const
   @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
   @empty: -> Const 'str', '', "''"
 
   @wrap: (val, name='(unknown)') ->
diff --git a/core/init.moon b/core/init.moon
index f0456c2..c91f0e4 100644
--- a/core/init.moon
+++ b/core/init.moon
@@ -7,9 +7,29 @@ import Scope from require 'core.scope'
 load_!
 
 import Cell, RootCell from require 'core.cell'
+import cell, program from require 'core.parsing'
 
 {
   :Const, :Cell, :RootCell
   :Op, :Action, :FnDef
   :Scope
+
+  parse: program\match
+  eval: do
+    class BuiltinRegistry
+      new: =>
+        @last = 1
+
+      register: (thing, tag) =>
+        with tag or Const.sym "builtin.#{@last}"
+          @last += 1
+
+    registry = BuiltinRegistry!
+
+    (str, inject) ->
+      scope = Scope.from_table require 'lib.builtin'
+      scope\use inject if inject
+
+      ast = assert (cell\match str), "failed to parse: #{str}"
+      Const.wrap ast\eval scope, registry
 }
diff --git a/core/parsing.moon b/core/parsing.moon
new file mode 100644
index 0000000..5186cb8
--- /dev/null
+++ b/core/parsing.moon
@@ -0,0 +1,56 @@
+import Const from require 'core.const'
+import Cell, RootCell from require 'core.cell'
+import R, S, P, V, C, Ct from require 'lpeg'
+
+-- whitespace
+wc = S ' \t\r\n'
+comment = P {
+  'comment',
+  expr: (P '(') * ((V 'expr') + (1 - P ')'))^0 * (P ')')
+  comment: (P '#(') * ((V 'expr') + (1 - P ')'))^0 * (P ')')
+}
+space  = (wc^1 * (comment * wc^1)^0) / 1 -- required whitespace
+mspace = (comment + wc)^0 / 1            -- optional whitespace
+
+-- atoms
+sym = ((R 'az', 'AZ') + (S '-_+*/.!?')) ^ 1 / Const\parse 'sym'
+
+strd = '"' * (C ((P '\\"') + (P '\\\\') + (1 - P '"'))^0) * '"' / Const\parse 'str', '\"'
+strq = "'" * (C ((P "\\'") + (P '\\\\') + (1 - P "'"))^0) * "'" / Const\parse 'str', '\''
+str = strd + strq
+
+digit = R '09'
+int = digit^1
+float = (digit^1 * '.' * digit^0) + (digit^0 * '.' * digit^1)
+num = (float + int) / Const\parse 'num'
+
+atom = num + sym + str
+
+expr = (V 'cell') + atom
+explist = Ct mspace * (V 'expr') * (space * (V 'expr'))^0 * mspace
+
+tag = (P '[') * atom * (P ']')
+cell = (P '(') * tag^-1 * (V 'explist') * (P ')') / Cell\parse
+
+root = P {
+  (V 'explist') / RootCell\parse
+  :expr, :explist, :cell
+}
+
+cell = P {
+  'cell'
+  :expr, :explist, :cell
+}
+
+program = root * -1
+
+{
+  :comment
+  :space
+  :atom
+  :expr
+  :explist
+  :cell
+  :root
+  :program
+}
diff --git a/core/scope.moon b/core/scope.moon
index a840ba7..ed4d67d 100644
--- a/core/scope.moon
+++ b/core/scope.moon
@@ -15,7 +15,7 @@ class Scope
       L\trace "found #{val} in #{@}"
       return val
 
-    start, rest = key\match '^(.-)/(.*)'
+    start, rest = key\match '^(.-)/(.+)'
 
     if not start
       return @parent and L\push -> @parent\get key
@@ -25,6 +25,7 @@ class Scope
     scope\getc!\get rest, "#{prefix}#{start}/"
 
   use: (other) =>
+    L\trace "using defs from #{other} in #{@}"
     for k, v in pairs other.values
       @values[k] = v