As I was watching WWDC19 Session: "LLDB: beyond "po" " I got confused about "p" command. In the session there was a following example to show how "p" command works:
// Struct for demonstration purposes
struct Trip {
var name: String
var destinations: [String]
let cruise = Trip (
name: "Mediterranean Cruise"
destinations: ["Sorrento", "Capri", "Taormina"])
Using "p" to get info about cruise instance:
(lldb) p cruise
(Travel.Trip) $R0 = {
name = "Mediterranean Cruise"
destinations = 3 values {
[0] = "Sorrento"
[1] = "Capri"
[2] = "Taormina"
}
}
I was following along and wrote the same code. But the output from LLDB turned out to be different:
(lldb) p cruise
(LLDB_Apple_Session_FollowAlong.Trip) {
name = "Mediterranean Cruise"
destinations = 3 values {
[0] = "Sorrento"
[1] = "Capri"
[2] = "Taormina"
}
}
As you can see LLDB didn't create a global variable R0 which I could later use in my debugging session and that seemed strange to me.
Then the presenter said the following:
"p" is just an alias for the "expression" command.
So, I tried to use the "expr" command to see if they're actually the same and they turned out to be different commands. The output I got from "expr" was the one I expected from "p":
(lldb) expr cruise
(LLDB_Apple_Session_FollowAlong.Trip) $R0 = {
name = "Mediterranean Cruise"
destinations = 3 values {
[0] = "Sorrento"
[1] = "Capri"
[2] = "Taormina"
}
}
Finally, my question is:
Am I wrong somewhere or did something change in LLDB regarding "p" and "expr" commands and if so, where could I get more information about the changes?
