From 75b67665d4b8161981478843268ddc2a5c5418b7 Mon Sep 17 00:00:00 2001
From: Chas Emerick <chas@cemerick.com>
Date: Fri, 21 Jan 2022 00:52:34 -0500
Subject: [PATCH] remove restriction against generating JSON with an atomic
 root value (fixes #121)

---
 CHANGES.md    | 2 ++
 lib/common.ml | 7 -------
 lib/pretty.ml | 6 +-----
 lib/write.ml  | 8 ++------
 4 files changed, 5 insertions(+), 18 deletions(-)

diff --git a/CHANGES.md b/CHANGES.md
index 43ae3640..3667d313 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -12,6 +12,8 @@
 - Removed `yojson-biniou` library
 - Removed deprecated `json` type aliasing type `t` which has been available
   since 1.6.0 (@Leonidas-from-XIV, #100).
+- Removed constraint that the "root" value being rendered (via either
+  `pretty_print` or `to_string`) must be an object or array. (@cemerick, #121)
 
 ### Add
 
diff --git a/lib/common.ml b/lib/common.ml
index df94ac11..d15e651b 100644
--- a/lib/common.ml
+++ b/lib/common.ml
@@ -72,13 +72,6 @@ let code_of_surrogate_pair i j =
 let utf8_of_surrogate_pair buf i j =
   utf8_of_code buf (code_of_surrogate_pair i j)
 
-let is_object_or_array x =
-  match x with
-      `List _
-    | `Assoc _ -> true
-    | _ -> false
-
-
 type lexer_state = {
   buf : Buffer.t;
     (* Buffer used to accumulate substrings *)
diff --git a/lib/pretty.ml b/lib/pretty.ml
index fef7c715..d3d4f405 100644
--- a/lib/pretty.ml
+++ b/lib/pretty.ml
@@ -49,11 +49,7 @@ and format_field std out (name, x) =
   Format.fprintf out "@[<hv2>%s: %a@]" (json_string_of_string name) (format std) x
 
 let pp ?(std = false) out x =
-  if std && not (is_object_or_array x) then
-    json_error
-      "Root is not an object or array as requested by the JSON standard"
-  else
-    Format.fprintf out "@[<hv2>%a@]" (format std) (x :> t)
+  Format.fprintf out "@[<hv2>%a@]" (format std) (x :> t)
 
 let to_string ?std x =
   Format.asprintf "%a" (pp ?std) x
diff --git a/lib/write.ml b/lib/write.ml
index 0bd87543..0e2090c9 100644
--- a/lib/write.ml
+++ b/lib/write.ml
@@ -418,12 +418,8 @@ and write_std_variant ob s o =
 
 
 let to_buffer ?(std = false) ob x =
-  if std then (
-    if not (is_object_or_array x) then
-      json_error "Root is not an object or array"
-    else
-      write_std_json ob x
-  )
+  if std then
+    write_std_json ob x
   else
     write_json ob x