Predicate functions return cadidate if true.

Instead of returning true or false, the predicate funcitons now return
an array that contains the candidate if it matches. This will allow us
to use the same function call for transforms.

inquiry.js

@@ -48,7 +48,8 @@
         args.push('return ' +  source + ')');
         struct.push((function (predicate) {
           return function (candidate, vargs) {
-            return predicate.apply(this, [ candidate._, candidate.o, candidate.i ].concat(vargs));
+            return predicate.apply(this, [ candidate._, candidate.o, candidate.i ].concat(vargs))
+                 ? [ candidate ] : []
           }
         })(Function.apply(Function, args)), []);
         break;
@@ -57,8 +58,8 @@
       case "[":
         struct.push((function (negate, subquery) {
           return function (candidate, args) {
-            var length = subquery.call(this, candidate, [ candidate.o, candidate.i ].concat(args)).length
-            return negate ? ! length : length;
+            var length = subquery.call(this, candidate, [ candidate.o, candidate.i ].concat(args)).length;
+            return (negate ? ! length : length) ? [ candidate ] : [];
           }
         })($[3] == '!', ($ = parse(rest, fixup, nesting + 1, "]"))[0]));
         rest = $[1].slice(1);
@@ -104,8 +105,8 @@
               for (j = object.length - 1; j > -1; --j) {
                 candidates.unshift({ o: object[j], _: [ j, expression[i][0] ].concat(_), p: [ object ].concat(path), i: j });
               }
-            } else if (expression[i][1].call(this, candidate, vargs)) {
-              stack.push(candidate);
+            } else {
+              stack.push.apply(stack, expression[i][1].call(this, candidate, vargs))
             }
           }
         } else {