❔ how to use "with"

Decoherence · 2023-10-06T22:08:18.839Z

the name with does not exist in the current context

T

Thinker•10/6/23, 10:08 PM

That's not how you use

with

with

with

with

T

Thinker•10/6/23, 10:08 PM

Remove the

new Human()

new Human()

new Human()

new Human() after

with

with

with

with

T

Thinker•10/6/23, 10:09 PM

Although you don't really need

with

with

with

with here anyway since this just looks like a regular object initializer

T

Thinker•10/6/23, 10:09 PM

Human human = new Human() { Sex = "female" };

Human human = new Human() { Sex = "female" };

Human human = new Human() { Sex = "female" };

Human human = new Human() { Sex = "female" };

D

DecoherenceOP•10/6/23, 10:09 PM

D

DecoherenceOP•10/6/23, 10:10 PM

"not a valid record type"

T

Thinker•10/6/23, 10:10 PM

Ah, yeah,

with

with

with

with only works on records and structs

D

DecoherenceOP•10/6/23, 10:10 PM

aw

unfortunate

T

Thinker•10/6/23, 10:11 PM

Although depends on what your

Human

Human

Human

Human class looks like, you could easily convert it to a record with little to no downsides

D

DecoherenceOP•10/6/23, 10:11 PM

D

DecoherenceOP•10/6/23, 10:12 PM

class Human
{
    private string? name;

    public string? Name 
    { 
        get =>  name; 
        set { Console.WriteLine("{0} has decided their name is {1}!", name, value); name = value; } 
    }
    public required string Sex { get; init; }
    protected int Age { get; set; }

    public void Grow()
    {
        Age++;
    }
}

class Human
{
    private string? name;

    public string? Name 
    { 
        get =>  name; 
        set { Console.WriteLine("{0} has decided their name is {1}!", name, value); name = value; } 
    }
    public required string Sex { get; init; }
    protected int Age { get; set; }

    public void Grow()
    {
        Age++;
    }
}

class Human
{
    private string? name;

    public string? Name 
    { 
        get =>  name; 
        set { Console.WriteLine("{0} has decided their name is {1}!", name, value); name = value; } 
    }
    public required string Sex { get; init; }
    protected int Age { get; set; }

    public void Grow()
    {
        Age++;
    }
}

class Human
{
    private string? name;

    public string? Name 
    { 
        get =>  name; 
        set { Console.WriteLine("{0} has decided their name is {1}!", name, value); name = value; } 
    }
    public required string Sex { get; init; }
    protected int Age { get; set; }

    public void Grow()
    {
        Age++;
    }
}

T

Thinker•10/6/23, 10:13 PM

You could really just change

class

class

class

class to

record

record

record

record if you wanted to

D

DecoherenceOP•10/6/23, 10:13 PM

hm

D

DecoherenceOP•10/6/23, 10:14 PM

yeah, it just amounted to doing that

T

Thinker•10/6/23, 10:14 PM

Also while you're at it, use string interpolation instead of that overload of

Console.WriteLine

Console.WriteLine

Console.WriteLine

Console.WriteLine

T

Thinker•10/6/23, 10:14 PM

And also put the setter on two lines

T

Thinker•10/6/23, 10:15 PM

set
{
    Console.WriteLine($"{name} has decided their name is {value}!");
    name = value;
}

set
{
    Console.WriteLine($"{name} has decided their name is {value}!");
    name = value;
}

set
{
    Console.WriteLine($"{name} has decided their name is {value}!");
    name = value;
}

set
{
    Console.WriteLine($"{name} has decided their name is {value}!");
    name = value;
}

D

DecoherenceOP•10/6/23, 10:15 PM

should it be

record class

record class

record class

record class instead of just

record

record

record

record to ensure its a reference type?

T

Thinker•10/6/23, 10:16 PM

record

record

record

record is always a reference type, but you can use

record class

record class

record class

record class if you feel it makes it clearer

T

Thinker•10/6/23, 10:16 PM

or if you use record structs a lot and you feel the need to clarify between what is a record struct and class

D

DecoherenceOP•10/6/23, 10:16 PM

may i ask for a tldr for what a record is?

T

Thinker•10/6/23, 10:17 PM

A record is a regular class or struct but with automatic reference equality, a shorter syntax, and other nicities like

with

with

with

with and automatic deconstruction.

D

DecoherenceOP•10/6/23, 10:17 PM

reference equality, meaning that if two records have the same data, they're considered equal?

T

Thinker•10/6/23, 10:17 PM

yep

T

Thinker•10/6/23, 10:18 PM

classes are by default compared by reference

D

DecoherenceOP•10/6/23, 10:19 PM

what about usual object methods like .Equals() etc

T

Thinker•10/6/23, 10:19 PM

those are overwritten by records

D

DecoherenceOP•10/6/23, 10:19 PM

oh, i assume same for ==

T

Thinker•10/6/23, 10:19 PM

yep

D

DecoherenceOP•10/6/23, 10:20 PM

before records were introduced what was the way to achieve this functionality?

D

DecoherenceOP•10/6/23, 10:20 PM

(also sorry for interrupting your explanations all the time)

T

Thinker•10/6/23, 10:20 PM

just writing everything out in its entirety

T

Thinker•10/6/23, 10:20 PM

records are pretty much just short-hand

T

Thinker•10/6/23, 10:21 PM

public class Person : IEquatable<Person>
{
    public string Name { get; init; }
    public int Age { get; init; }

    public Person(string name, int age)
    {
        Name = name;
        Age = age;
    }

    public bool Equals(Person? other) =>
        other is not null &&
        Name == other.Name &&
        Age == other.Age;
    
    public override bool Equals(object? obj) =>
        Equals(obj as Person);

    public override int GetHashCode() =>
        HashCode.Combine(Name, Age);

    public override string ToString() =>
        $"Person {{ Name = {Name}, Age = {Age} }}";

    public void Deconstruct(out string name, out int age)
    {
        name = Name;
        age = Age;
    }

    public static bool operator ==(Person a, Person b) => a.Equals(b);
    public static bool operator !=(Person a, Person b) => !a.Equals(b);
}

public class Person : IEquatable<Person>
{
    public string Name { get; init; }
    public int Age { get; init; }

    public Person(string name, int age)
    {
        Name = name;
        Age = age;
    }

    public bool Equals(Person? other) =>
        other is not null &&
        Name == other.Name &&
        Age == other.Age;
    
    public override bool Equals(object? obj) =>
        Equals(obj as Person);

    public override int GetHashCode() =>
        HashCode.Combine(Name, Age);

    public override string ToString() =>
        $"Person {{ Name = {Name}, Age = {Age} }}";

    public void Deconstruct(out string name, out int age)
    {
        name = Name;
        age = Age;
    }

    public static bool operator ==(Person a, Person b) => a.Equals(b);
    public static bool operator !=(Person a, Person b) => !a.Equals(b);
}

public class Person : IEquatable<Person>
{
    public string Name { get; init; }
    public int Age { get; init; }

    public Person(string name, int age)
    {
        Name = name;
        Age = age;
    }

    public bool Equals(Person? other) =>
        other is not null &&
        Name == other.Name &&
        Age == other.Age;
    
    public override bool Equals(object? obj) =>
        Equals(obj as Person);

    public override int GetHashCode() =>
        HashCode.Combine(Name, Age);

    public override string ToString() =>
        $"Person {{ Name = {Name}, Age = {Age} }}";

    public void Deconstruct(out string name, out int age)
    {
        name = Name;
        age = Age;
    }

    public static bool operator ==(Person a, Person b) => a.Equals(b);
    public static bool operator !=(Person a, Person b) => !a.Equals(b);
}

public class Person : IEquatable<Person>
{
    public string Name { get; init; }
    public int Age { get; init; }

    public Person(string name, int age)
    {
        Name = name;
        Age = age;
    }

    public bool Equals(Person? other) =>
        other is not null &&
        Name == other.Name &&
        Age == other.Age;
    
    public override bool Equals(object? obj) =>
        Equals(obj as Person);

    public override int GetHashCode() =>
        HashCode.Combine(Name, Age);

    public override string ToString() =>
        $"Person {{ Name = {Name}, Age = {Age} }}";

    public void Deconstruct(out string name, out int age)
    {
        name = Name;
        age = Age;
    }

    public static bool operator ==(Person a, Person b) => a.Equals(b);
    public static bool operator !=(Person a, Person b) => !a.Equals(b);
}

This can be written as

public record Person(string Name, int Age);

public record Person(string Name, int Age);

public record Person(string Name, int Age);

public record Person(string Name, int Age);

D

DecoherenceOP•10/6/23, 10:22 PM

o: wow

D

DecoherenceOP•10/6/23, 10:22 PM

C# is amazing

D

DecoherenceOP•10/6/23, 10:22 PM

offtopic, but in your opinion, do you think humans are records?

D

DecoherenceOP•10/6/23, 10:23 PM

if two people have the same name, age

T

Thinker•10/6/23, 10:23 PM

Personally I would probably represent a human/person as a record, although depends on how complex you want the structure to be

D

DecoherenceOP•10/6/23, 10:23 PM

hmm.. what would be a quality humans have that makes them unique? their dna? lmao

D

DecoherenceOP•10/6/23, 10:23 PM

maybe i could give each human a hash

T

Thinker•10/6/23, 10:24 PM

Yeah like in the programming sense you could probably assume two people are the same if they have the same values, although if you were to strive for a "complete" model of a human then yeah you'd probably compare by DNA or something

D

DecoherenceOP•10/6/23, 10:24 PM

i see. i guess it would depend on what spec is

T

Thinker•10/6/23, 10:25 PM

yeah, usually referred to as "domain modeling"

D

DecoherenceOP•10/6/23, 10:26 PM

thank you!

T

Thinker•10/6/23, 10:26 PM

np

A

Accord•10/7/23, 10:29 PM

Was this issue resolved? If so, run

/close

/close

otherwise I will mark this as stale and this post will be archived until there is new activity.

❔ how to use "with"

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