de/fn, loop parameter lists use square brackets

2 files changed, 17 insertions, 13 deletions

diff --git a/alv/builtins.moon b/alv/builtins.moon
index 84978f1..6e36c7e 100644
--- a/alv/builtins.moon
+++ b/alv/builtins.moon
@@ -12,7 +12,7 @@ import
 import Constant from require 'alv.result'
 import Error from require 'alv.error'
 import RTNode from require 'alv.rtnode'
-import Cell from require 'alv.cell'
+import Cell, ArrayCell from require 'alv.cell'
 import Dummy from require 'alv.dummy'
 import Scope from require 'alv.scope'
 import Tag from require 'alv.tag'
@@ -194,7 +194,7 @@ fn = Constant.meta
   meta:
     name: 'fn'
     summary: "Declare a function."
-    examples: { '(fn (p1 [p2…]) body-expr)' }
+    examples: { '(fn [p1 p2…] body-expr)' }
     description: "
 The symbols `p1`, `p2`, ... will resolve to the arguments passed when the
 function is invoked."
@@ -205,7 +205,7 @@ function is invoked."
       assert #tail == 2, "'fn' takes exactly two arguments"
       { params, body } = tail
 
-      assert params.__class == Cell, "'fn's first argument has to be an expression"
+      assert params.__class == ArrayCell, "'fn's first argument has to be a [parmeter list]"
       param_symbols = for param in *params.children
         assert param.type == T.sym, "function parameter declaration has to be a symbol"
         param
@@ -220,7 +220,7 @@ defn = Constant.meta
   meta:
     name: 'defn'
     summary: "Define a function."
-    examples: { '(defn name-sym (p1 [p2…]) body-expr)' }
+    examples: { '(defn name-sym [p1 p2…] body-expr)' }
     description: "
 Declare a function and define it as `name-sym` in the current scope.
 The symbols `p1`, `p2`, ... will resolve to the arguments passed when the
@@ -233,7 +233,7 @@ function is invoked."
       { name, params, body } = tail
 
       name = name\unwrap T.sym
-      assert params.__class == Cell, "'defn's second argument has to be an expression"
+      assert params.__class == ArrayCell, "'defn's second argument has to be a [parameter list]"
       param_symbols = for param in *params.children
         assert param.type == T.sym, "function parameter declaration has to be a symbol"
         param
@@ -636,7 +636,7 @@ loop = Constant.meta
   meta:
     name: 'loop'
     summary: "Loop on arbitrary data via recursion."
-    examples: { '(loop (k1 v1 [k2 v2…]) body)' }
+    examples: { '(loop [k1 v1 [k2 v2…]] body)' }
     description: "
 Defines a recursive loop function `*recur*` with parameters `k1`, `k2`, … and
 function body `body`, then invokes it immediately with arguments `v1`, `v2`, …
@@ -644,7 +644,7 @@ function body `body`, then invokes it immediately with arguments `v1`, `v2`, …
 Inside the `body`, `(recur)` is used to recursively restart loop evaluation
 with a different set of arguments, e.g. to sum the first `5` integers:
 
-    (loop (n 5)
+    (loop [n 5]
       (if (= n 0)
         0
         (+ n (recur (n - 1)))))"
@@ -655,7 +655,7 @@ with a different set of arguments, e.g. to sum the first `5` integers:
       assert #tail == 2, "'loop' takes exactly two arguments"
       { binds, body } = tail
 
-      assert binds.__class == Cell, "loops bindings have to be an cell"
+      assert binds.__class == ArrayCell, "loops bindings have to be a [parameter list]"
       assert #binds.children % 2 == 0, "key without binding in loop binding"
 
       names = {}
diff --git a/alv/cell.moon b/alv/cell.moon
index 8d1e5f6..989d4ad 100644
--- a/alv/cell.moon
+++ b/alv/cell.moon
@@ -190,9 +190,11 @@ class ArrayCell extends RootCell
   tail: => @children
   stringify: => '[' .. super! .. ']'
 
-  new: (...) =>
-    Cell.__init @, ...
+  eval: (...) =>
     assert #@children > 0, Error 'syntax', "array literal can't be empty"
+    super ...
+
+  new: (...) => Cell.__init @, ...
 
 --- @type StructCell
 class StructCell extends RootCell
@@ -200,10 +202,12 @@ class StructCell extends RootCell
   tail: => @children
   stringify: => '{' .. super! .. '}'
 
-  new: (...) =>
-    Cell.__init @, ...
+  eval: (...) =>
     assert #@children > 0, Error 'syntax', "struct literal can't be empty"
-    assert #@children % 2 == 0, Error 'syntax', "struct literal can't have uneven number values"
+    assert #@children % 2 == 0, Error 'syntax', "struct literal must have even number of values"
+    super ...
+
+  new: (...) => Cell.__init @, ...
 
 --- @type TemplateString
 class TemplateString extends Cell