Add support for table constructors.

Author: treeform

src/jsony.nim

@@ -550,6 +550,8 @@ proc dumpHook*(s: var string, v: string)
 proc dumpHook*(s: var string, v: char)
 proc dumpHook*(s: var string, v: tuple)
 proc dumpHook*(s: var string, v: enum)
+type t[T] = tuple[a:string, b:T]
+proc dumpHook*[N, T](s: var string, v: array[N, t[T]])
 proc dumpHook*[N, T](s: var string, v: array[N, T])
 proc dumpHook*[T](s: var string, v: seq[T])
 proc dumpHook*(s: var string, v: object)
@@ -749,6 +751,19 @@ proc dumpHook*(s: var string, v: object) =
       inc i
   s.add '}'
 
+proc dumpHook*[N, T](s: var string, v: array[N, t[T]]) =
+  s.add '{'
+  var i = 0
+  # Normal objects.
+  for (k, e) in v:
+    if i > 0:
+      s.add ','
+    s.dumpHook(k)
+    s.add ':'
+    s.dumpHook(e)
+    inc i
+  s.add '}'
+
 proc dumpHook*(s: var string, v: ref) =
   if v == nil:
     s.add "null"

tests/test_tables.nim

@@ -47,3 +47,13 @@ block:
   doAssert v["a"].color == "red"
   doAssert v["b"].color == "green"
   doAssert v["c"].color == "blue"
+
+block:
+  doAssert {"j":10,"s":20,"o":100,"n":5000}.toJson() ==
+    """{"j":10,"s":20,"o":100,"n":5000}"""
+
+  doAssert {"j":"a","s":"b","o":"c","n":"d"}.toJson() ==
+    """{"j":"a","s":"b","o":"c","n":"d"}"""
+
+  doAssert [{"j":"a"}].toJson() ==
+    """[{"j":"a"}]"""