Change from "sealed" to "protected".

Author: davidlehn

lib/context.js

@@ -67,12 +67,12 @@ api.process = ({activeCtx, localCtx, options,
 
     // reset to initial context
     if(ctx === null) {
-      // We can't nullify if there are sealed terms and we're
+      // We can't nullify if there are protected terms and we're
       // not in a term definition
       if(!propertyTermDefinition &&
-         Object.keys(activeCtx.sealed).length !== 0) {
+         Object.keys(activeCtx.protected).length !== 0) {
         throw new JsonLdError(
-          'Tried to nullify a context with sealed terms outside of ' +
+          'Tried to nullify a context with protected terms outside of ' +
           'a term definition.',
           'jsonld.SyntaxError',
           {code: 'invalid context nullification'});
@@ -193,10 +193,10 @@ api.process = ({activeCtx, localCtx, options,
       defined['@language'] = true;
     }
 
-    // handle @sealed; determine whether this sub-context is declaring
-    // all its terms to be "sealed" (exceptions can be made on a
+    // handle @protected; determine whether this sub-context is declaring
+    // all its terms to be "protected" (exceptions can be made on a
     // per-definition basis)
-    defined['@sealed'] = ctx['@sealed'] || false;
+    defined['@protected'] = ctx['@protected'] || false;
 
     // process all other keys
     for(const key in ctx) {
@@ -251,13 +251,11 @@ api.createTermDefinition = (activeCtx, localCtx, term, defined) => {
       {code: 'invalid term definition', context: localCtx});
   }
 
-  // Is this term currently sealed?
-  // Then redefining it here is an error!
-  if(activeCtx.sealed[term]) {
+  if(activeCtx.protected[term]) {
     throw new JsonLdError(
-      'Invalid JSON-LD syntax; tried to redefine a sealed term.',
+      'Invalid JSON-LD syntax; tried to redefine a protected term.',
       'jsonld.SyntaxError',
-      {code: 'sealed term redefinition', context: localCtx, term});
+      {code: 'protected term redefinition', context: localCtx, term});
   }
 
   // remove old mapping
@@ -299,7 +297,7 @@ api.createTermDefinition = (activeCtx, localCtx, term, defined) => {
 
   // JSON-LD 1.1 support
   if(api.processingMode(activeCtx, 1.1)) {
-    validKeys.push('@context', '@nest', '@prefix', '@sealed');
+    validKeys.push('@context', '@nest', '@prefix', '@protected');
   }
 
   for(const kw in value) {
@@ -404,14 +402,14 @@ api.createTermDefinition = (activeCtx, localCtx, term, defined) => {
     }
   }
 
-  // Handle term sealing
-  if('@sealed' in value) {
-    if(value['@sealed']) {
-      activeCtx.sealed[term] = true;
+  // Handle term protection
+  if('@protected' in value) {
+    if(value['@protected']) {
+      activeCtx.protected[term] = true;
     }
-  } else if('@sealed' in defined) {
-    if(defined['@sealed']) {
-      activeCtx.sealed[term] = true;
+  } else if('@protected' in defined) {
+    if(defined['@protected']) {
+      activeCtx.protected[term] = true;
     }
   }
 
@@ -687,7 +685,7 @@ api.getInitialContext = options => {
     inverse: null,
     getInverse: _createInverseContext,
     clone: _cloneActiveContext,
-    sealed: {}
+    protected: {}
   };
   // TODO: consider using LRU cache instead
   if(INITIAL_CONTEXT_CACHE.size === INITIAL_CONTEXT_CACHE_MAX_SIZE) {
@@ -863,7 +861,7 @@ api.getInitialContext = options => {
     child.clone = this.clone;
     child.inverse = null;
     child.getInverse = this.getInverse;
-    child.sealed = util.clone(this.sealed);
+    child.protected = util.clone(this.protected);
     if('@language' in this) {
       child['@language'] = this['@language'];
     }
@@ -973,9 +971,9 @@ api.isKeyword = v => {
     case '@omitDefault':
     case '@prefix':
     case '@preserve':
+    case '@protected':
     case '@requireAll':
     case '@reverse':
-    case '@sealed':
     case '@set':
     case '@type':
     case '@value':