Godot: Weird error "get_node"

[git2013vb]

Godot version:
3.2 beta3
OS/device including version:
win7-64
Issue description:
I have this error :Error 15,1: The method "get_node" isn't declared in the current class.
in this line:
onready var pos_spawn_enemy_mid:Vector2 = $Ground/SpawnPivots/EnemyMid.position

in terminal i have this error:

* daemon not running; starting now at tcp:5037
erasing C:\Users\homev3\AppData\Roaming/Godot/projects/topdown-656ff94ce70ac8286e098a1814b517d0/filesystem_update4
SCRIPT ERROR: GDScript::reload: Parse Error: The method "get_node" isn't declared in the current class.
          At: res://src/maps/Map.gd:15
ERROR: reload: Method/Function Failed, returning: ERR_PARSE_ERROR
   At: modules/gdscript/gdscript.cpp:576
* daemon started successfully
Running: C:\Users\homev3\Desktop\Godot_v3.2-beta3_win64.exe --path c:/Users/homev3/Documents/GoDot/release/projects/topdown
007 --allow_focus_steal_pid 19708 --position 1920,0
Godot Engine v3.2.beta3.official - https://godotengine.org
OpenGL ES 3.0 Renderer: GeForce GT 650M/PCIe/SSE2

ERROR: debug_get_stack_level_instance: Condition ' _debug_parse_err_line >= 0 ' is true. returned: __null
   At: modules/gdscript/gdscript_editor.cpp:338

in debug dock I have this error:

E 0:00:00.745   debug_get_stack_level_instance: Condition ' _debug_parse_err_line >= 0 ' is true. returned: __null
  <C++ Source>  modules/gdscript/gdscript_editor.cpp:338 @ debug_get_stack_level_instance()

But I have no idea if is related

Steps to reproduce:
I moved the $Ground
Minimal reproduction project:
NA

[akien-mga]

What class does Map.gd inherit from? get_node is a Node method. Most likely your class doesn't inherit Node or a derivate class.

@bojidar-bg @vnen Maybe we can make the error message clearer when $ is used in a non-Node class?

[git2013vb]

What class does Map.gd inherit from? get_node is a Node method. Most likely your class doesn't inherit Node or a derivate class.

@bojidar-bg @vnen Maybe we can make the error message clearer when $ is used in a non-Node class?

You right! I have nothing in first line but I had a extends Node2D before moving it

[KoBeWi]

From my experience, this usually happens when inherited script has an error, so it can't be properly loaded.

[MJBrune]

I'm getting this currently with an inheritance depth of 3. Does inheritance just start to break down after a certain depth?

[MJBrune]

restarting the editor immediately took care of it... 🤷‍♂️

[dweremeichik]

I just ran into the same issue. The class I was inheriting from was also called "Map" not sure if that has anything to do with it. As @MJBrune stated a restart of the editor did the trick.