Don't store tree's hidden children in a separate array

Just mark hidden trees as such, and skip them when
pretty-printing a tree

spec/runtime/languages/arithmetic/errors.txt

@@ -10,6 +10,6 @@ recovers from errors inside parenthesized expressions
 =====================================================
 x + (y * + z) * 5
 ---
-(expression (sum
+(sum
     (variable)
-    (product (group (ERROR '+')) (number))))
+    (product (group (ERROR '+')) (number)))

spec/runtime/languages/arithmetic/main.txt

@@ -3,51 +3,47 @@ parses numbers
 ===================
 5
 ---
-(expression (number))
+(number)
 
 ===================
 parses variables
 ===================
 x
 ---
-(expression (variable))
+(variable)
 
 ===================
 parses products
 ===================
 x * x
 ---
-(expression (product
-    (variable)
-    (variable)))
+(product (variable) (variable))
 
 ===================
 parses sums
 ===================
 x + x
 ---
-(expression (sum
-    (variable)
-    (variable)))
+(sum (variable) (variable))
 
 ===============================================
 binds multiplication more tightly than addition
 ===============================================
 a * b + c * d
 ---
-(expression (sum
+(sum
     (product (variable) (variable))
-    (product (variable) (variable))))
+    (product (variable) (variable)))
 
 ============================
 parses exponents
 ============================
 x + y * z^(a + b)
 ---
-(expression (sum
+(sum
     (variable)
     (product
         (variable)
         (exponent
             (variable)
-            (group (sum (variable) (variable)))))))
+            (group (sum (variable) (variable))))))

spec/runtime/languages/javascript/literals.txt

@@ -39,7 +39,7 @@ var x = {
             (statement_block (var_declaration (identifier) (identifier)))))))
 
 ==========================================
-parses comments z
+parses comments
 ==========================================
 // this is the beginning of the script.
 // here we go.
@@ -57,14 +57,14 @@ var thing = {
 (program
     (comment)
     (comment)
-    (var_declaration (identifier) (object
+    (program (var_declaration (identifier) (object
         (comment)
         (comment)
         (identifier) (function_expression
             (formal_parameters (identifier) (comment))
             (statement_block
                 (comment)
-                (expression_statement (function_call (identifier))))))))
+                (expression_statement (function_call (identifier)))))))))
 
 ==========================================
 parses comments within expressions

spec/runtime/languages/json/errors.txt

@@ -17,24 +17,24 @@ recovers from errors inside arrays
 ==========================================
 [1, , 2]
 ---
-(value (array
+(array
     (number)
     (ERROR <EOF>)
-    (number)))
+    (number))
 
 ==========================================
 recovers from errors inside objects
 ==========================================
 { "key1": 1, oops }
 ---
-(value (object (string) (number) (ERROR 'o')))
+(object (string) (number) (ERROR 'o'))
 
 ==========================================
 recovers from errors inside nested objects
 ==========================================
 { "key1": { "key2": 1, 2 }, [, "key3": 3 }
 ---
-(value (object
+(object
     (string) (object (string) (number) (ERROR '2'))
     (ERROR '[')
-    (string) (number)))
+    (string) (number))

spec/runtime/languages/json/main.txt

@@ -3,14 +3,14 @@ parses floating point numbers
 =============================
 3.14
 ---
-(value (number))
+(number)
 
 ===================
 parses empty arrays
 ===================
 []
 ---
-(value (array))
+(array)
 
 ===================
 parses arrays
@@ -23,19 +23,19 @@ parses arrays
     { "stuff": "good" }
 ]
 ---
-(value (array
+(array
     (number)
     (null)
     (true)
     (false)
-    (object (string) (string))))
+    (object (string) (string)))
 
 ====================
 parses empty objects
 ====================
 {}
 ---
-(value (object))
+(object)
 
 ===================
 parses long objects
@@ -45,8 +45,7 @@ parses long objects
 	"key2": 1
 }
 ---
-(value (object
+(object
 	(string) (string)
-	(string) (number)
-))
+	(string) (number))