diff options
| -rw-r--r-- | swift.html.markdown | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/swift.html.markdown b/swift.html.markdown index 2fbbe544..c6d2a8af 100644 --- a/swift.html.markdown +++ b/swift.html.markdown @@ -445,7 +445,10 @@ class MyShape: Rect { func grow() { sideLength += 2 - + + // Place a question mark after an optional property, method, or + // subscript to gracefully ignore a nil value and return nil + // instead of throwing a runtime error ("optional chaining"). if let allow = self.delegate?.canReshape?() { // test for delegate then for method self.delegate?.reshaped?() |