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Merge pull request #935 from keito/master

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Explain Optional Chaining
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Adam Bard
2015-01-20 22:57:49 +00:00
parent 6915f5bfd0 7a55b4a9b1
commit e6930e4b67
1 changed files with 4 additions and 1 deletions
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swift.html.markdown
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@@ -445,7 +445,10 @@ class MyShape: Rect {
func grow() { func grow() {
sideLength += 2 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?() { if let allow = self.delegate?.canReshape?() {
// test for delegate then for method // test for delegate then for method
self.delegate?.reshaped?() self.delegate?.reshaped?()