Separated Matcher.

packages/minimongo/common.js

@@ -0,0 +1,30 @@
+import {LocalCollection} from './local_collection.js';
+
+export function isIndexable (obj) {
+  return Array.isArray(obj) || LocalCollection._isPlainObject(obj);
+}
+
+export function isNumericKey (s) {
+  return /^[0-9]+$/.test(s);
+}
+
+// Returns true if this is an object with at least one key and all keys begin
+// with $.  Unless inconsistentOK is set, throws if some keys begin with $ and
+// others don't.
+export function isOperatorObject (valueSelector, inconsistentOK) {
+  if (!LocalCollection._isPlainObject(valueSelector))
+    return false;
+
+  var theseAreOperators = undefined;
+  Object.keys(valueSelector).forEach(function (selKey) {
+    var thisIsOperator = selKey.substr(0, 1) === '$';
+    if (theseAreOperators === undefined) {
+      theseAreOperators = thisIsOperator;
+    } else if (theseAreOperators !== thisIsOperator) {
+      if (!inconsistentOK)
+        throw new Error(`Inconsistent operator: ${JSON.stringify(valueSelector)}`);
+      theseAreOperators = false;
+    }
+  });
+  return !!theseAreOperators;  // {} has no operators
+}

packages/minimongo/package.js

@@ -24,6 +24,9 @@ Package.onUse(api => {
 
   api.addFiles('minimongo.js');
   api.addFiles('minimongo_server.js', 'server');
+
+  // api.mainModule('client_main.js', 'client');
+  // api.mainModule('server_main.js', 'server');
 });
 
 Package.onTest(api => {