Expand JSON literals.

Author: gkellogg

lib/context.js

@@ -1114,6 +1114,7 @@ api.isKeyword = v => {
     case '@graph':
     case '@id':
     case '@index':
+    case '@json':
     case '@language':
     case '@list':
     case '@nest':

lib/expand.js

@@ -23,7 +23,8 @@ const {
   expandIri: _expandIri,
   getContextValue: _getContextValue,
   isKeyword: _isKeyword,
-  process: _processContext
+  process: _processContext,
+  processingMode: _processingMode
 } = require('./context');
 
 const {
@@ -289,6 +290,8 @@ api.expand = ({
         'Invalid JSON-LD syntax; only strings may be language-tagged.',
         'jsonld.SyntaxError',
         {code: 'invalid language-tagged value', element: rval});
+    } else if(_processingMode(activeCtx, 1.1) && types.includes('@json') && types.length === 1) {
+      // Any value of @value is okay if @type: @json
     } else if(!types.every(t =>
       (_isAbsoluteIri(t) && !(_isString(t) && t.indexOf('_:') === 0) ||
       _isEmptyObject(t)))) {
@@ -494,16 +497,7 @@ function _expandObject({
         'jsonld.SyntaxError', {code: 'invalid @graph value', value});
     }
 
-    // @value must not be an object or an array (unless framing)
     if(expandedProperty === '@value') {
-      if((_isObject(value) || _isArray(value)) && !options.isFrame) {
-        throw new JsonLdError(
-          'Invalid JSON-LD syntax; "@value" value must not be an ' +
-          'object or an array.',
-          'jsonld.SyntaxError',
-          {code: 'invalid value object value', value});
-      }
-
       _addValue(
         expandedParent, '@value', value, {propertyIsArray: options.isFrame});
       continue;
@@ -753,6 +747,20 @@ function _expandObject({
     });
   }
 
+  // @value must not be an object or an array (unless framing) or if @type is @json
+  if('@value' in element) {
+    const value = element['@value'];
+    if(element['@type'] === '@json' && _processingMode(activeCtx, 1.1)) {
+      // Sllow any value, to be verified when the object is fully expanded and the @type is @json.
+    } else if((_isObject(value) || _isArray(value)) && !options.isFrame) {
+      throw new JsonLdError(
+        'Invalid JSON-LD syntax; "@value" value must not be an ' +
+        'object or an array.',
+        'jsonld.SyntaxError',
+        {code: 'invalid value object value', value});
+    }
+  }
+
   // expand each nested key
   for(const key of nests) {
     const nestedValues = _isArray(element[key]) ? element[key] : [element[key]];