mac: Checking for existence of a key in a map using the 'in' keyword causes a segfault about v HOT 7 CLOSED

mut eb := new_event_bus[string]()
It's wrong to use it here.
We should use shared eb := new_event_bus[string]().

from v.

I cannot reproduce the problem on my Linux machine. How did you trigger it? When I run the program after compiling as shown, it just hangs until I hit Ctrl-C:

[jalon@7950x v]$ ./v -g -o vdbg cmd/v && ./vdbg event_bus_trial.v
[jalon@7950x v]$ ./event_bus_trial
^C
[jalon@7950x v]$

from v.

It is reproducible on macos:
0[15:17:22]@m1: (master) /opt/v $ v -cc clang run ee.v
signal 11: segmentation fault
0 libsystem_platform.dylib 0x00000001805af584 _sigtramp + 56
1 ee 0x00000001045542cc map_key_to_index + 36
2 ee 0x000000010453c3a4 map_exists + 32
3 ee 0x000000010457bdcc main__EventBus_T_string_subscribe_T_string + 112
4 ee 0x000000010457c070 main__main + 84
5 ee 0x000000010457c760 main + 84
6 dyld 0x00000001801f60e0 start + 2360
139[15:17:34]@m1: (master) /opt/v $

from v.

mut eb := new_event_bus[string]() It's wrong to use it here. We should use shared eb := new_event_bus[string]().

That is right.
I think we should add a checker error, for mut eb, used for methods with shared receivers.

struct Abc { x int }
fn f(shared a Abc) { lock a { println(a.x) } }
fn (shared a Abc) m(){ lock a { println(a.x) } }
// mut a := Abc{}
// f(a) // checker error

mut b := Abc{} // if b is not mutable, there is a checker error, telling the user to declare `b` with `mut` to make it mutable; the message can be changed too, to mention that it should be `shared` too
b.m() // no checker error, but it is better to have one, similar to the `f(a)` case above

from v.

Yes, we should add a checker error.

from v.

I've removed shared receivers from V. Passing tests, will be live soon.

from v.

(as discussed on discord)

from v.