Xcode debugger reporting Swift dictionaries as empty (po reports {})

问题

When I wait until Xcode 6.1.1 hits a breakpoint after this line

let metrics = ["leading" : 15.0, "size" : 44.0]

and then type po metrics the debugger reports (after several seconds delay) {}, which seems wrong. po metrics.count reports 2, which is right.

Is this a feature or a bug?

UPDATE The problem appears when debugging on a physical device (iPhone 5), e.g. not on a simulator (e.g. iPhone 6 Plus).

回答1:

Did you try doing this way?

let metrics:NSDictionary? = ["leading" : 15.0, "size" : 44.0]

println(metrics!)

来源：https://stackoverflow.com/questions/28124159/xcode-debugger-reporting-swift-dictionaries-as-empty-po-reports