add documentation info

cmd/moon/main.go

@@ -10,53 +10,61 @@ moon file is syntactically valid.
 
 The following is taken to be the contents of a file named ex.moon:
 
+  # ------------------------------------------------------------------------------
+  # example config format
+  #
+  # this is a working draft of things that are valid in a new config language to
+  # replace json as a config language for Go projects.
+  #
+  # comments are a thing now!
+  # ------------------------------------------------------------------------------
+
   # the whole document is implicitly a namespace, so you can set key value pairs
   # at the top level.
-  first_name: "jordan"
-  last_name: "orelli"
+  first_name: jordan
+  last_name: orelli
 
   # lists of things should be supported
   items: [
-      "one"
+      one
       2
       3.4
-      ["five" 6 7.8]
+      [five; 6 7.8]
   ]
 
   # objects should be supported
-  hash: {key: "value" other_key: "other_value"}
+  hash: {key: value; other_key: other_value}
 
   other_hash: {
-      key_1: "one"
+      key_1: one
       key_2: 2
       key_3: 3.4
-      key_4: ["five" 6 7.8]
+      key_4: [five; 6 7.8]
   }
 
-  # we may reference an item that was defined earlier
-  repeat_hash: hash
+  # we may reference an item that was defined earlier using a sigil
+  repeat_hash: @hash
 
   # items can be hidden.  i.e., they're only valid in the parse and eval stage as
   # intermediate values internal to the config file; they are *not* visible to
   # the host program.  This is generally useful for composing larger, more
   # complicated things.
-  .hidden_item: "it has a value"
-
-  visible_item: .hidden_item
+  @hidden_item: it has a value
+  visible_item: @hidden_item
 
-  .person_one: {
-      name: "the first name here"
+  @person_one: {
+      name: the first name here
       age: 28
-      hometown: "crooklyn"
+      hometown: crooklyn
   }
 
-  .person_two: {
-      name: "the second name here"
+  @person_two: {
+      name: the second name here
       age: 30
-      hometown: "tha bronx"
+      hometown: tha bronx
   }
 
-  people: [.person_one .person_two]
+  people: [@person_one @person_two]
 
 
 Subcommands