gegerlan/Gentle-Love-Quest — comment on commit df0d69e00680286acb28cf3f24897421b0509727
File:  line 0
By gegerlan:

When you run a script in the game interpreter (e.g. using the script command, or entering something in the script box for a condition), all it does is run an eval on the string you provided. Since the eval runs inside the Game_Interpreter object, any method you've defined for the interpreter is directly accessible from this context.
e.g. by adding the following script

class Game_Interpreter
FOO = "BAR"
def HelloWorld
return FOO
@x = "y"
end
end

You can just access the method and class variables directly from the script.

Script: p HelloWorld() # method call
Script: p FOO # constant
Script: p @x # variable