def read_world(filename)
File.open(filename) do |file| file.each_line do |line|
if line != "KarelWorld"
key, street, avenue, other = line.split
street, avenue, other = street.to_i, avenue.to_i, other.to_i
if key == "beepers"
place_beepers(street, avenue, other)
elsif key == "eastwestwalls"
while avenue <= other
place_wall_north_of(street, avenue)
avenue += 1
end
elsif key == "northsouthwalls"
street, avenue = avenue, street
while street <= other
place_wall_east_of(street, avenue)
street += 1
end
end
end
end
end
nil
end