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xcodestringlldbsummarynsindexpath

NSIndexPath: a useful lldb summary string

While debugging with lldb in Xcode I would like to see in a debugger window a simple summary string for NSIndexPath objects. Something like:

indexPath = (NSIndexPath *) { section=2 : row=0 }

would be much more helpful then what is displayed by lldb by default:

indexPath = (NSIndexPath *) [NSIndexPath * @ scalar section]

I did try many summary string formatters written to my .lldbinit file, with these among them:

type summary add NSIndexPath --summary-string '${var.section}'

type summary add NSIndexPath --summary-string '${[var section]}'

type summary add NSIndexPath --summary-string '[${var section}]'

type summary add NSIndexPath --summary-string '[${var} section]'

The result for first three is:

indexPath NSIndexPath * error: summary string parsing error 0x08e309a0

and for the last one is:

indexPath NSIndexPath * [NSIndexPath * @ scalar section] 0x08a45b80

which is not much more helpful neither.

Do you know how to force lldb to display some more useful summary string for NSIndexPath?

Solution

  • (lldb) type summary add NSIndexPath -s "${var%@}"

    This will essentially show you the same output that

    (lldb) po myIndexPath

    would - at the cost of running an expression every time you're looking at an index path, which may or may not be what you want