Browse Questions
  • LLDB is the debugger built into Xcode.
  • A memory leak is memory that is allocated but never freed — usually from retain cycles.
  • Swift's async/await is directly supported in XCTest — mark your test function as async throws and await the result.
  • Classic OOP centers on classes and inheritance hierarchies — behavior is shared by subclassing a base class.

Answer: LLDB is the debugger built into Xcode. When paused at a breakpoint, you can type commands in the console to inspect and modify the running app.

Most useful commands:

# Print object description
po viewModel
po viewModel.items.count

# Print raw value
p frame.size.width

# Modify a value while paused
expr isLoading = true
expr (void)[self.tableView reloadData]

# Print backtrace (call stack)
bt

# Move up/down the call stack
up
down

# List all local variables
frame variable

# Continue execution
c

# Step over next line
n

# Step into function call
s

# Step out of current function
finish

# Set a breakpoint from console
breakpoint set --name viewDidLoad
br s -n "URLSession"