I'm having trouble getting Xcode to show me the underlying memory of a
I can control-click on any of those and choose 'View Memory of "data"' etc, but none of them show the memory block I'm looking for. (I know this because I print()
the first few bytes accessed via the subscript operator data[0]
etc.)
_representation
shows me address0x0
slice
(1) shows me memory but not what I'm looking forslice
(2) shows me the same as the previous onelowerBound
shows me the same as the previous twoupperBound
shows me some other memory not what I'm looking forstorage
shows me address0x0
I'm used to languages more like C where I'd have a pointer or array.
I've also tried stepping through the disassembly while viewing the registers where the code is indexing into the data but I'm not used to ARM asm and can't seem to find the address I'm looking for that way either.
(No, it's not the memory at 0x40006000022804b0
)
desired behavior
View the bytes encapsulated by the Data
specific problem or error
Every component of the Data
that the debugger presents to me shows either nothing or bytes other than what I'm looking for when I use the context menu "View Memory of ..."
and the shortest code necessary to reproduce the problem
This problem is not about my code. It's about how to get the Xcode debugger to show me the underlying memory of an object.
CodePudding user response:
Data
has multiple different backing storage strategies (e.g. one for slicing, one for bridging to Objective C, etc.)
0x40006000022804b0
contains a Foundation.__DataStorage
object. It has a _bytes property which is where the actual buffer is. It's exposed -[NSData bytes]
, which you can print out for debugging purposes