Why not inherit from List T

0 votes

When planning out my programs, I often start with a chain of thought like so:

A football team is just a list of football players. Therefore, I should represent it with:

var football_team = new List<FootballPlayer>();

The ordering of this list represent the order in which the players are listed in the roster.

But I realize later that teams also have other properties, besides the mere list of players, that must be recorded. For example, the running total of scores this season, the current budget, the uniform colors, a string representing the name of the team, etc..

So then I think:

Okay, a football team is just like a list of players, but additionally, it has a name (a string) and a running total of scores (an int). .NET does not provide a class for storing football teams, so I will make my own class. The most similar and relevant existing structure is List<FootballPlayer>, so I will inherit from it:

class FootballTeam : List<FootballPlayer> 
{ 
    public string TeamName; 
    public int RunningTotal 
}

Nov 20, 2020 in Python by anonymous
• 10,420 points
25 views

1 answer to this question.

0 votes

There are some good answers here. I would add to them the following points.

What is the correct C# way of representing a data structure, which, "logically" (that is to say, "to the human mind") is just a list of things with a few bells and whistles?

Ask any ten non-computer-programmer people who are familiar with the existence of football to fill in the blank:

A football team is a particular kind of _____

Did anyone say "list of football players with a few bells and whistles", or did they all say "sports team" or "club" or "organization"? Your notion that a football team is a particular kind of list of players is in your human mind and your human mind alone.

List<T> is a mechanism. A football team is a business object -- that is, an object that represents some concept that is in the business domain of the program. Don't mix those! A football team is a kind of team; it has a roster, a roster is a list of players. A roster is not a particular kind of list of players. A roster is a list of players. So make a property called Roster that is a List<Player>. And make it ReadOnlyList<Player> while you're at it unless you believe that everyone who knows about a football team gets to delete players from the roster.

answered Nov 20, 2020 by Gitika
• 65,870 points

Related Questions In Python

0 votes
0 answers

How to remove elements from a list that may or may not be present?

In case I want to remove some ...READ MORE

Jun 27, 2019 in Python by Nisa
• 1,090 points
163 views
0 votes
1 answer

How can I convert a list of dictionaries from a CSV into a JSON object in Python?

You could try using the AST module. ...READ MORE

answered Apr 17, 2018 in Python by anonymous
2,161 views
0 votes
1 answer

List of lines from a file

with open(fname) as f: ...READ MORE

answered Apr 30, 2018 in Python by Nietzsche's daemon
• 4,260 points
89 views
0 votes
1 answer

Python join: why is it string.join(list) instead of list.join(string)?

950down voteaccepted It's because any iterable can be ...READ MORE

answered May 15, 2018 in Python by aryya
• 7,420 points
184 views
0 votes
2 answers
+1 vote
2 answers

how can i count the items in a list?

Syntax :            list. count(value) Code: colors = ['red', 'green', ...READ MORE

answered Jul 6, 2019 in Python by Neha
• 330 points

edited Jul 8, 2019 by Kalgi 1,833 views
0 votes
0 answers
0 votes
4 answers

How do I remove an element from a list by index in Python?

1886 Use del and specify the index of the element ...READ MORE

answered Dec 11, 2020 in Python by Gitika
• 65,870 points
54,147 views
+1 vote
5 answers