Document "import" warning in Unified module (ocaml#412)

* also: add build deps count
* also: pin bsconfig schema version

Author: kanishka-work

site/bsconfig.json

@@ -1,5 +1,5 @@
 {
-  "$schema": "https://raw.githubusercontent.com/rescript-lang/rescript-compiler/master/docs/docson/build-schema.json",
+  "$schema": "https://raw.githubusercontent.com/rescript-lang/rescript-compiler/9.0.0/docs/docson/build-schema.json",
   "name": "ocamlorg",
   "namespace": true,
   "reason": {

site/package.json

@@ -27,12 +27,14 @@
     "next:debug": "NODE_OPTIONS='--inspect' next dev",
     "watch": "concurrently --raw \"bsb -make-world -w\" \"next dev\" ",
     "watch-and-serve": "concurrently --raw \"bsb -make-world -w\" \"next dev\" \"http-server out\"",
-    "build": "bsb -clean-world -make-world && next build && next export",
-    "start-test-server": "http-server out"
+    "build": "bsb -clean-world -make-world && next build && next export && yarn total-dependencies-check",
+    "start-test-server": "http-server out",
+    "total-dependencies-check": "(test $(grep '^[a-zA-Z@].*:$' yarn.lock | wc -l) -lt 500 && echo ok) || (echo too many deps && exit 1) "
   },
   "scriptsDescription": {
-    "build": "at present, next export is only used to ensure that we strictly use static site functionality",
-    "start-test-server": "Vercel deployments use next start, but this command tests running a pure static site. TODO: use npx from Makefile instead."
+    "build": "At present, next export is only used to ensure that we strictly use static site functionality.",
+    "start-test-server": "Vercel deployments use next start, but this command tests running a pure static site. TODO: use npx from Makefile instead.",
+    "total-dependencies-check": "Test, approximately, whether the current transitiive dependencies has grown significantly."
   },
   "devDependencies": {
     "@tailwindcss/typography": "^0.4.0",

site/src/Unified.res

@@ -1,3 +1,16 @@
+// The following code causes a warning. My limited understanding is that the warning
+// occurs because there is a mismatch between ReScript's assumptions about the version
+// of Javascript being used and the actual version of Javascript used in NextJS. Currently,
+// we have ReScript configured to target the ES6 version of Javascript. This is the emerging standard. At the same time,
+// there are open issues in NextJS requesting ES6 support, but NextJS does not
+// currently evaluate Javascript in an ES6 context. NextJS uses CommonJS when
+// evaluating Javascript. The warning occurs because ReScript uses an external validator
+// on the generated Javascript and the external validator notes that using "import" in
+// the syntax below is not valid in ES6. The syntax is valid in CommonJS, which means
+// the code will successfully run in NextJS.
+// This warning will hopefully be resolved by September of 2021, if
+// NextJS proceeds to lift its restriction on using ES6. The status of this issue
+// can be tracked in Github issue #298.
 %%raw(`
 const MdastUtilToStringInternal = (await import('mdast-util-to-string')).toString
 `)