diff --git a/src/field/FieldClassMatcher.js b/src/field/FieldClassMatcher.js
index 1d0153c..6ecc9ef 100644
--- a/src/field/FieldClassMatcher.js
+++ b/src/field/FieldClassMatcher.js
@@ -102,7 +102,7 @@ module.exports = Class( 'FieldClassMatcher',
                     // default to visible; note that, if we've encountered any
                     // "all index" situations (scalars), then we must only be
                     // true if the scalar value was true
-                    vis[ i ] = (
+                    vis[ i ] = +(
                         ( !hasall || all )
                         && ( ( vis[ i ] === undefined )
                             ? 1
diff --git a/test/field/FieldClassMatcherTest.js b/test/field/FieldClassMatcherTest.js
index 00940c9..1196bdd 100644
--- a/test/field/FieldClassMatcherTest.js
+++ b/test/field/FieldClassMatcherTest.js
@@ -260,8 +260,7 @@ describe( 'FieldClassMatcher', () =>
                 foo: {
                     all:     false,
                     any:     false,
-                    // FIXME: should be [ 0, 0 ]
-                    indexes: [ false, false ],
+                    indexes: [ 0, 0 ],
                 },
             },
         },