Xcode debugger (lldb) get object description from memory address

Little-known fact: It is now possible, in Xcode, while paused in the debugger, to introspect the notification center to learn what objects are registered to receive what notifications:

(lldb) po NotificationCenter.default

Name, Object, Observer, Options
com.apple.accessibility.reduce.motion.status, 0x10b126190, 0x7fc795700140, 1001
com.apple.accessibility.asst.scanner.status, 0x10b126190, 0x7fc795700140, 1001
// ... etc. ...

Very nice, but how do I get from the memory address 0x7fc795700140 to learning what object that is?

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  • 2 Solutions Collect From Internet About “Xcode debugger (lldb) get object description from memory address”

    po works for addresses (In Objective-C/Mac context, at least)


    (lldb) po [NSNotificationCenter defaultCenter]

    NSWindowDidResizeNotification, 0x7fff9a0e98e0, 0x6100001246a0, 1400

    (lldb) po 0x6100001246a0

    ExpandOneView: 0x6100001246a0

    The Swift equivalent of Phillip’s answer is:

    (lldb) expr -l objc -O -- 0x7fc795700140
    <UIApplication: 0x7fc795700140>