Update page 'Day 4 Homework'
+205
@@ -0,0 +1,205 @@
|
||||
As a recap, we've talked about how numbers work, how characters work, how characters are combined into text via lexers and parsers, and how numbers and text are combined via operators in custom classes:
|
||||
|
||||
```
|
||||
Numbers ------------------------> Operators -> ?
|
||||
Characters --(Lexers/Parsers) --> Operators -> ?
|
||||
```
|
||||
|
||||
Today's homework is to think about how to design classes, or what the industry calls "object-oriented design." You have to be careful to minimize complexity when designing public interfaces and APIs to your code, otherwise this happens:
|
||||
|
||||
https://github.com/EnterpriseQualityCoding/FizzBuzzEnterpriseEdition/blob/uinverse/src/main/java/com/seriouscompany/business/java/fizzbuzz/packagenamingpackage/impl/loop/LoopCondition.java
|
||||
|
||||
Remember fizzbuzz? This is a satirical version built using every object-oriented pattern in the book. There is an actual book on the subject, which is widely respected throughout the industry, and in some cases misused to overcomplicate code:
|
||||
|
||||
https://en.wikipedia.org/wiki/Design_Patterns
|
||||
|
||||
The assignment for today is to think about some everyday thing you interact with, such as an elevator, a pet, or anything which has tangible and measurable *inputs* and *outputs*. There are three files to look at in the `simulation` directory in this repository:
|
||||
|
||||
* SimulationRunner: a program to run simulation classes.
|
||||
* Simulation: the interface definition for a simulation.
|
||||
* HotdogSimulation: a class simulating a hot dog.
|
||||
|
||||
Design two versions of this object with the following shared criteria:
|
||||
|
||||
* Define the start, stop, tick, get_uses, and use methods.
|
||||
* Ensure that the object expires when a reasonable number of ticks have passed.
|
||||
|
||||
One version of the object should be very simple, such as the hot dog example.
|
||||
|
||||
The other version of the object should be overly complicated, with verbs such as `weigh` to get its mass, `mood` to get its mood, `price_tag` to have it return its estimated value, and `go_to_moon` to send the object to the moon (in the case of the pet, it would probably explode and `use()` should return `False`). Try to define at least 20 different verbs you could use on the object, with associated instance variables to track its state so the verbs interact correctly. For example, a `throw` verb on a hot dog should reduce its mass, because some of its condiments will end up on the target.
|
||||
|
||||
Although it would be preferred to create a Python file that can be run under the simulator, a text specification is also acceptable. The important thing is for the object to have a consistent model of its state which accurately represents what would happen in real life when methods (verbs) are applied to it.
|
||||
|
||||
```
|
||||
class Toaster:
|
||||
def __init__(self):
|
||||
self.ticks_left = 10
|
||||
self.is_on = False
|
||||
|
||||
def get_uses(self):
|
||||
return {
|
||||
'toast': "Put bread in the toaster to make toast."
|
||||
}
|
||||
|
||||
def start(self):
|
||||
print("Toaster started.")
|
||||
|
||||
def use(self, *args, **kwargs):
|
||||
if 'toast' in args:
|
||||
if not self.is_on:
|
||||
print("Turn the toaster on first!🔌")
|
||||
return True
|
||||
|
||||
print("Toasting...")
|
||||
self.ticks_left -= 1
|
||||
if self.ticks_left == 0:
|
||||
print("Toasting complete! 🍞")
|
||||
return False
|
||||
|
||||
return True
|
||||
|
||||
def tick(self):
|
||||
return True
|
||||
|
||||
def stop(self):
|
||||
print("Toaster stopped. ⏸")
|
||||
```
|
||||
|
||||
```
|
||||
class AdvancedToaster:
|
||||
def __init__(self):
|
||||
self.ticks_left = 10
|
||||
self.is_on = False
|
||||
self.toastiness = 0
|
||||
self.bread_count = 0
|
||||
self.crumb_tray = []
|
||||
self.temperature = None
|
||||
self.weight = 1.5 # kg
|
||||
self.voltage = 120 # V
|
||||
self.power = 750 # W
|
||||
self.materials = ['stainless steel', 'plastic', 'copper']
|
||||
self.dimensions = {'length': 30, 'width': 20, 'height': 25} # cm
|
||||
self.color = 'silver'
|
||||
self.price = 50 # USD
|
||||
|
||||
def get_uses(self):
|
||||
return {
|
||||
'turn_on': "Turn on the toaster.",
|
||||
'turn_off': "Turn off the toaster.",
|
||||
'insert_bread': "Insert bread into the toaster.",
|
||||
'eject_bread': "Eject bread from the toaster.",
|
||||
'increase_toastiness': "Increase the level of toastiness.",
|
||||
'decrease_toastiness': "Decrease the level of toastiness.",
|
||||
'add_bread': "Add a slice of bread to the toaster.",
|
||||
'remove_bread': "Remove a slice of bread from the toaster.",
|
||||
'toast': "Toast the bread in the toaster.",
|
||||
'empty_crumb_tray': "Empty the crumb tray.",
|
||||
'weigh': "Weigh the toaster.",
|
||||
'measure_voltage': "Measure the voltage of the toaster.",
|
||||
'measure_power': "Measure the power of the toaster.",
|
||||
'get_materials': "Get the materials the toaster is made of.",
|
||||
'get_dimensions': "Get the dimensions of the toaster.",
|
||||
'get_color': "Get the color of the toaster.",
|
||||
'get_price_tag': "Get the estimated value of the toaster."
|
||||
}
|
||||
|
||||
def start(self):
|
||||
print("Toaster started.")
|
||||
|
||||
def set_temperature(self, temperature):
|
||||
self.temperature = temperature
|
||||
print(f"Toaster temperature set to {temperature} degrees Celsius.")
|
||||
|
||||
def get_temperature(self):
|
||||
if self.temperature is not None:
|
||||
print(f"Toaster temperature is {self.temperature} degrees Celsius.")
|
||||
else:
|
||||
print("Toaster temperature has not been set yet.")
|
||||
|
||||
def use(self, *args, **kwargs):
|
||||
if 'turn_on' in args:
|
||||
self.is_on = True
|
||||
print("Toaster turned on.")
|
||||
|
||||
elif 'turn_off' in args:
|
||||
self.is_on = False
|
||||
print("Toaster turned off.")
|
||||
|
||||
elif 'insert_bread' in args:
|
||||
if not self.is_on:
|
||||
print("Turn the toaster on first!")
|
||||
return True
|
||||
|
||||
if self.bread_count > 2:
|
||||
print("Too many bread slices! Maximum is 2.")
|
||||
return True
|
||||
|
||||
self.bread_count += 1
|
||||
print(f"{self.bread_count} bread slice{'s' if self.bread_count > 1 else ''} inserted.")
|
||||
|
||||
elif 'eject_bread' in args:
|
||||
if self.bread_count == 0:
|
||||
print("No bread slices to eject.")
|
||||
return True
|
||||
|
||||
self.bread_count -= 1
|
||||
print("Bread slice ejected.")
|
||||
|
||||
elif 'decrease_toastiness' in args:
|
||||
if self.toastiness > 0:
|
||||
self.toastiness -= 1
|
||||
print(f"Toastiness decreased to {self.toastiness}.")
|
||||
|
||||
elif 'add_bread' in args:
|
||||
if self.bread_count < 2:
|
||||
self.bread_count += 1
|
||||
print(f"{self.bread_count} slice(s) of bread added to the toaster.")
|
||||
|
||||
elif 'remove_bread' in args:
|
||||
if self.bread_count > 0:
|
||||
self.bread_count -= 1
|
||||
print(f"{self.bread_count} slice(s) of bread removed from the toaster.")
|
||||
|
||||
elif 'toast' in args:
|
||||
if self.is_on and self.bread_count > 0:
|
||||
print("Toasting bread...")
|
||||
for i in range(self.toastiness):
|
||||
print("Tick...")
|
||||
print("Bread toasted!")
|
||||
self.bread_count -= 1
|
||||
elif not self.is_on:
|
||||
print("Toaster is not turned on.")
|
||||
elif self.bread_count == 0:
|
||||
print("Toaster does not contain any bread.")
|
||||
else:
|
||||
print(f"DEBUG:Invalid use of the toaster.")
|
||||
return False
|
||||
|
||||
elif 'empty_crumb_tray' in args:
|
||||
self.crumb_tray = []
|
||||
print("Crumb tray emptied.")
|
||||
|
||||
def weigh(self):
|
||||
print(f"The weight of the toaster is {self.weight} kg.")
|
||||
|
||||
def measure_voltage(self):
|
||||
# Method to measure the voltage of the toaster
|
||||
print(f"The voltage of the toaster is {self.voltage} V.")
|
||||
|
||||
def measure_power(self):
|
||||
# Method to measure the power of the toaster
|
||||
print(f"The power of the toaster is {self.power} W.")
|
||||
|
||||
|
||||
defer get_materials(self):
|
||||
print(f"The toaster is made of: {', '.join(self.materials)}.")
|
||||
|
||||
defer get_dimensions(self):
|
||||
print(f"The dimensions of the toaster are: {self.dimensions['length']} cm x {self.dimensions['width']} cm x {self.dimensions['height']} cm.")
|
||||
|
||||
defer get_color(self):
|
||||
print(f"The color of the toaster is {self.color}.")
|
||||
|
||||
defer get_price_tag(self):
|
||||
print(f"The estimated value of the toaster is {self.price_tag}.")
|
||||
```
|
||||
Reference in New Issue
Block a user