diff --git a/platform/darwin/src/MGLFillExtrusionStyleLayer.h b/platform/darwin/src/MGLFillExtrusionStyleLayer.h
index 84f6bedde4a..c4fb9aa77ea 100644
--- a/platform/darwin/src/MGLFillExtrusionStyleLayer.h
+++ b/platform/darwin/src/MGLFillExtrusionStyleLayer.h
@@ -46,7 +46,7 @@ typedef NS_ENUM(NSUInteger, MGLFillExtrusionTranslationAnchor) {
  layer.sourceLayerIdentifier = "building"
  layer.fillExtrusionHeight = MGLStyleValue(interpolationMode: .identity, sourceStops: nil, attributeName: "height", options: nil)
  layer.fillExtrusionBase = MGLStyleValue(interpolationMode: .identity, sourceStops: nil, attributeName: "min_height", options: nil)
- layer.predicate = NSPredicate(format: "extrude == TRUE")
+ layer.predicate = NSPredicate(format: "extrude == 'true'")
  mapView.style?.addLayer(layer)
  ```
  */
diff --git a/platform/darwin/test/MGLDocumentationExampleTests.swift b/platform/darwin/test/MGLDocumentationExampleTests.swift
index 6d2dc597a94..48e6b17f445 100644
--- a/platform/darwin/test/MGLDocumentationExampleTests.swift
+++ b/platform/darwin/test/MGLDocumentationExampleTests.swift
@@ -168,7 +168,7 @@ class MGLDocumentationExampleTests: XCTestCase, MGLMapViewDelegate {
         layer.sourceLayerIdentifier = "building"
         layer.fillExtrusionHeight = MGLStyleValue(interpolationMode: .identity, sourceStops: nil, attributeName: "height", options: nil)
         layer.fillExtrusionBase = MGLStyleValue(interpolationMode: .identity, sourceStops: nil, attributeName: "min_height", options: nil)
-        layer.predicate = NSPredicate(format: "extrude == TRUE")
+        layer.predicate = NSPredicate(format: "extrude == 'true'")
         mapView.style?.addLayer(layer)
         //#-end-example-code