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What is the binary operator of Function Monoids in example of JavaScript

What is the most efficient way to deep clone an object in JavaScript?Which equals operator (== vs ===) should be used in JavaScript comparisons?What is the scope of variables in JavaScript?JavaScript closure inside loops – simple practical exampleWhat is the !! (not not) operator in JavaScript?Set a default parameter value for a JavaScript functionWhat is the JavaScript version of sleep()?What is (functional) reactive programming?What does “use strict” do in JavaScript, and what is the reasoning behind it?What is the 'new' keyword in JavaScript?

1

0

In this article Function Monoids are introduced with C# code and Haskell Type definition.

A function a -> b is a monoid if b is a monoid. This means that
you can combine two functions with the same type. In an
object-oriented context, it means that you can combine two methods
with the same signature into one method as long as the return type
forms a monoid.

Generalisation

While the above C# code is only an example, the general rule is that
any function that returns a monoid is itself a monoid. In Haskell,
this rule is articulated in the standard library:

instance Monoid b => Monoid (a -> b)

This means that for any monoid b, a function a -> b is also
(automatically) a monoid.

The problem is the example in C# is too specific about "GUID" and I have no idea what the author trying to do in the code, and the Haskell Type Definition is merely the type definition.

What is an example code in JavaScript to implement this Function Monoids?

cf)
Why is instance Monoid b => Monoid (a -> b) in base?

javascript functional-programming monoids

share|improve this question

edited Mar 21 at 21:30

Bergi

380k64582916

asked Mar 21 at 21:15

user11239932

• 
  
  
  

  
  3
  

  
  
  
  
  
  

  
  
  Given that javascript doesn't have a sophisticated enough type system, it's rather hard to translate. "Being a monoid" is not something that can be expressed as a runtime value. I would recommend to study Haskell to understand what the article means if you are interested in this.
  
  – Bergi
  Mar 21 at 21:27
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  I don't agree. To implement Monoids in JavaScript, type system is not required at all. The same goes to Mondas.
  
  – user11239932
  Mar 21 at 21:30
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  The C# example isn't specific on GUIDs at all. The meat of the article is the Combine function, which you should be able to translate into javascript even without any C# knowledge. CountPrimes and CountLetters are just used as examples of functions to be used as arguments to Combine.
  
  – Bergi
  Mar 21 at 21:33
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  @tbookq I'm writing comments because I haven't yet answered your question "What is an example code in JavaScript to implement this Function Monoids?". I'm writing comments to suggest ways to improve your question so that I can properly answer it with a helpful and understandable post.
  
  – Bergi
  Mar 21 at 21:39
  
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  @tbookq Please edit your question to include an arbitrary implementation of a monoid as an example (and to demonstrate your level of knowledge), and I will write an appropriate answer. I don't want to write an answer that is useless to you, but you will need to provide more information. It's you who wants other to help him.
  
  – Bergi
  Mar 21 at 22:11
  

  
  
  
  

 | 
show 3 more comments

1

0

In this article Function Monoids are introduced with C# code and Haskell Type definition.

A function a -> b is a monoid if b is a monoid. This means that
you can combine two functions with the same type. In an
object-oriented context, it means that you can combine two methods
with the same signature into one method as long as the return type
forms a monoid.

Generalisation

While the above C# code is only an example, the general rule is that
any function that returns a monoid is itself a monoid. In Haskell,
this rule is articulated in the standard library:

instance Monoid b => Monoid (a -> b)

This means that for any monoid b, a function a -> b is also
(automatically) a monoid.

The problem is the example in C# is too specific about "GUID" and I have no idea what the author trying to do in the code, and the Haskell Type Definition is merely the type definition.

What is an example code in JavaScript to implement this Function Monoids?

cf)
Why is instance Monoid b => Monoid (a -> b) in base?

javascript functional-programming monoids

share|improve this question

edited Mar 21 at 21:30

Bergi

380k64582916

asked Mar 21 at 21:15

user11239932

• 
  
  
  

  
  3
  

  
  
  
  
  
  

  
  
  Given that javascript doesn't have a sophisticated enough type system, it's rather hard to translate. "Being a monoid" is not something that can be expressed as a runtime value. I would recommend to study Haskell to understand what the article means if you are interested in this.
  
  – Bergi
  Mar 21 at 21:27
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  I don't agree. To implement Monoids in JavaScript, type system is not required at all. The same goes to Mondas.
  
  – user11239932
  Mar 21 at 21:30
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  The C# example isn't specific on GUIDs at all. The meat of the article is the Combine function, which you should be able to translate into javascript even without any C# knowledge. CountPrimes and CountLetters are just used as examples of functions to be used as arguments to Combine.
  
  – Bergi
  Mar 21 at 21:33
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  @tbookq I'm writing comments because I haven't yet answered your question "What is an example code in JavaScript to implement this Function Monoids?". I'm writing comments to suggest ways to improve your question so that I can properly answer it with a helpful and understandable post.
  
  – Bergi
  Mar 21 at 21:39
  
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  @tbookq Please edit your question to include an arbitrary implementation of a monoid as an example (and to demonstrate your level of knowledge), and I will write an appropriate answer. I don't want to write an answer that is useless to you, but you will need to provide more information. It's you who wants other to help him.
  
  – Bergi
  Mar 21 at 22:11
  

  
  
  
  

 | 
show 3 more comments

In this article Function Monoids are introduced with C# code and Haskell Type definition.

A function a -> b is a monoid if b is a monoid. This means that
you can combine two functions with the same type. In an
object-oriented context, it means that you can combine two methods
with the same signature into one method as long as the return type
forms a monoid.

Generalisation

While the above C# code is only an example, the general rule is that
any function that returns a monoid is itself a monoid. In Haskell,
this rule is articulated in the standard library:

instance Monoid b => Monoid (a -> b)

This means that for any monoid b, a function a -> b is also
(automatically) a monoid.

The problem is the example in C# is too specific about "GUID" and I have no idea what the author trying to do in the code, and the Haskell Type Definition is merely the type definition.

What is an example code in JavaScript to implement this Function Monoids?

cf)
Why is instance Monoid b => Monoid (a -> b) in base?

javascript functional-programming monoids

share|improve this question

edited Mar 21 at 21:30

Bergi

380k64582916

asked Mar 21 at 21:15

user11239932

share|improve this question

edited Mar 21 at 21:30

Bergi

380k64582916

asked Mar 21 at 21:15

user11239932

share|improve this question

edited Mar 21 at 21:30

Bergi

380k64582916

asked Mar 21 at 21:15

user11239932

edited Mar 21 at 21:30

Bergi

380k64582916

edited Mar 21 at 21:30

Bergi

380k64582916

2 Answers
2

active

oldest

votes

1

Monoid Laws

identity law:
combine (identity, a) == combine (a, identity)

associativity law:
combine (a, combine (b, c)) == combine (combine (a, b), c)

We can implement an identity element (identity) and binary operation (combine) for functions -

// identity element
const identity =
 x => x

// binary operation
const combine = (a, b) =>
 x => a (b (x))
 
// sample functions
const a =
 x => x + 3
 
const b =
 x => x - 1

const c =
 x => x * x

// uphold laws
console.log
 ( combine (identity, a) (2) === combine (a, identity) (2)
 , combine (a, combine (b, c)) (2) === combine (combine (a, b), c) (2)
 )
 
// => true
// => true

The binary operation and identity element is different depending on your domain. See the table on Wikipedia for more insight on how to implement the identity element and binary operation for various sets.

Of course you are not limited to those domains. Your custom type may have various binary operations and identity elements that satisfy the monoid laws. If the laws are upheld, your type belongs to the monoid category.

share|improve this answer

answered Mar 21 at 23:00

user633183user633183

71.9k21143184

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks, but x => a (b (x)) is composition of function, that is "endomorphism-monoid" which is not what this topic is about. blog.ploeh.dk/2017/11/13/endomorphism-monoid In Haskell, it's callled Endo Monoid.
  
  – user11239932
  Mar 21 at 23:50
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  The question is "What is the binary operator of Function Monoids in example of JavaScript?". This answer explains that any identity element and binary operation that satisfies the monoid laws forms a monoid. The answer also shows an example of a function monoid in JavaScript. The linked Wikipedia table shows other pairings that form monoids as well. I guess your question title is wrong or maybe you don't understand what you're asking.
  
  – user633183
  Mar 22 at 0:07
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Well, I wrote a book about FunctionalProgramming published by one of the major publishing company in Japan. So, I know what I'm talking about. The question refers a specific Monoid with example and the title corresponds to it. I know Monoid well, and not asking here Monoid Law etc. that I also know well. Your answer is irreverent since it does not correspond to the question. Sorry.
  
  – user11239932
  Mar 22 at 0:18
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  You've been very quick to dismiss others and assert yourself. I can see you're very proud of your credentials, possibly to a fault. Did you bother to look at the credentials of the people offering their help? Bergi is one of the most knowledgeable contributors on this topic here on SO; also patient and respectful. You seem to know exactly what you want, so I'll leave you to find it.
  
  – user633183
  Mar 22 at 0:27
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  The point is my question is resolved. This is Q&A site. To answer own question is not prohibited so did I. Perhaps it's a good idea you also you investigate your behavior saying "your question title is wrong", the fact is nothing wrong presenting the concrete example and definition. It's simple and clear "endomorphism-monoid" in your answer or identiy funciton tihng is out of topic here.
  
  – user11239932
  Mar 22 at 0:33
  

  
  
  
  

 | 
show 2 more comments

1

It's important to know that being able to combine things doesn't necessarily mean they are a monoid. For something to be a Monoid, it must have associativity, left identity, and right identity.

C#:

public static Func<Guid, int> Combine(
 Func<Guid, int> f,
 Func<Guid, int> g)

 return x => f(x) + g(x);

JS:

function combine(f,g) 
 return x => f(x) + g(x)


function addOne(x) 
 return x + 1;


function addTwo(x) 
 return x + 2;


let newFunction = combine(addOne, addTwo);
let result = newFunction(0);
console.log(result)

share|improve this answer

edited Mar 21 at 23:28

answered Mar 21 at 21:50

Nick AcostaNick Acosta

1,6361019

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks, I probably should ask not just combine operation since this does not make sense at least, and yes it would generate a error. Small working code please in S.O.Snippet.
  
  – user11239932
  Mar 21 at 21:55
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  combine is a function that accepts two arguments, these arguments are assumed to be functions in this case. combine will actually return a new function that takes one argument. Inside this new function, each argument, f and g will be applied to x and their results will be added together. I hope this make it easier to understand.
  
  – Nick Acosta
  Mar 21 at 23:21
  
  

  
  
  
  

add a comment | 

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1

Monoid Laws

identity law:
combine (identity, a) == combine (a, identity)

associativity law:
combine (a, combine (b, c)) == combine (combine (a, b), c)

We can implement an identity element (identity) and binary operation (combine) for functions -

// identity element
const identity =
 x => x

// binary operation
const combine = (a, b) =>
 x => a (b (x))
 
// sample functions
const a =
 x => x + 3
 
const b =
 x => x - 1

const c =
 x => x * x

// uphold laws
console.log
 ( combine (identity, a) (2) === combine (a, identity) (2)
 , combine (a, combine (b, c)) (2) === combine (combine (a, b), c) (2)
 )
 
// => true
// => true

The binary operation and identity element is different depending on your domain. See the table on Wikipedia for more insight on how to implement the identity element and binary operation for various sets.

Of course you are not limited to those domains. Your custom type may have various binary operations and identity elements that satisfy the monoid laws. If the laws are upheld, your type belongs to the monoid category.

share|improve this answer

answered Mar 21 at 23:00

user633183user633183

71.9k21143184

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks, but x => a (b (x)) is composition of function, that is "endomorphism-monoid" which is not what this topic is about. blog.ploeh.dk/2017/11/13/endomorphism-monoid In Haskell, it's callled Endo Monoid.
  
  – user11239932
  Mar 21 at 23:50
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  The question is "What is the binary operator of Function Monoids in example of JavaScript?". This answer explains that any identity element and binary operation that satisfies the monoid laws forms a monoid. The answer also shows an example of a function monoid in JavaScript. The linked Wikipedia table shows other pairings that form monoids as well. I guess your question title is wrong or maybe you don't understand what you're asking.
  
  – user633183
  Mar 22 at 0:07
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Well, I wrote a book about FunctionalProgramming published by one of the major publishing company in Japan. So, I know what I'm talking about. The question refers a specific Monoid with example and the title corresponds to it. I know Monoid well, and not asking here Monoid Law etc. that I also know well. Your answer is irreverent since it does not correspond to the question. Sorry.
  
  – user11239932
  Mar 22 at 0:18
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  You've been very quick to dismiss others and assert yourself. I can see you're very proud of your credentials, possibly to a fault. Did you bother to look at the credentials of the people offering their help? Bergi is one of the most knowledgeable contributors on this topic here on SO; also patient and respectful. You seem to know exactly what you want, so I'll leave you to find it.
  
  – user633183
  Mar 22 at 0:27
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  The point is my question is resolved. This is Q&A site. To answer own question is not prohibited so did I. Perhaps it's a good idea you also you investigate your behavior saying "your question title is wrong", the fact is nothing wrong presenting the concrete example and definition. It's simple and clear "endomorphism-monoid" in your answer or identiy funciton tihng is out of topic here.
  
  – user11239932
  Mar 22 at 0:33
  

  
  
  
  

 | 
show 2 more comments

1

Monoid Laws

identity law:
combine (identity, a) == combine (a, identity)

associativity law:
combine (a, combine (b, c)) == combine (combine (a, b), c)

We can implement an identity element (identity) and binary operation (combine) for functions -

// identity element
const identity =
 x => x

// binary operation
const combine = (a, b) =>
 x => a (b (x))
 
// sample functions
const a =
 x => x + 3
 
const b =
 x => x - 1

const c =
 x => x * x

// uphold laws
console.log
 ( combine (identity, a) (2) === combine (a, identity) (2)
 , combine (a, combine (b, c)) (2) === combine (combine (a, b), c) (2)
 )
 
// => true
// => true

The binary operation and identity element is different depending on your domain. See the table on Wikipedia for more insight on how to implement the identity element and binary operation for various sets.

Of course you are not limited to those domains. Your custom type may have various binary operations and identity elements that satisfy the monoid laws. If the laws are upheld, your type belongs to the monoid category.

share|improve this answer

answered Mar 21 at 23:00

user633183user633183

71.9k21143184

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks, but x => a (b (x)) is composition of function, that is "endomorphism-monoid" which is not what this topic is about. blog.ploeh.dk/2017/11/13/endomorphism-monoid In Haskell, it's callled Endo Monoid.
  
  – user11239932
  Mar 21 at 23:50
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  The question is "What is the binary operator of Function Monoids in example of JavaScript?". This answer explains that any identity element and binary operation that satisfies the monoid laws forms a monoid. The answer also shows an example of a function monoid in JavaScript. The linked Wikipedia table shows other pairings that form monoids as well. I guess your question title is wrong or maybe you don't understand what you're asking.
  
  – user633183
  Mar 22 at 0:07
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Well, I wrote a book about FunctionalProgramming published by one of the major publishing company in Japan. So, I know what I'm talking about. The question refers a specific Monoid with example and the title corresponds to it. I know Monoid well, and not asking here Monoid Law etc. that I also know well. Your answer is irreverent since it does not correspond to the question. Sorry.
  
  – user11239932
  Mar 22 at 0:18
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  You've been very quick to dismiss others and assert yourself. I can see you're very proud of your credentials, possibly to a fault. Did you bother to look at the credentials of the people offering their help? Bergi is one of the most knowledgeable contributors on this topic here on SO; also patient and respectful. You seem to know exactly what you want, so I'll leave you to find it.
  
  – user633183
  Mar 22 at 0:27
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  The point is my question is resolved. This is Q&A site. To answer own question is not prohibited so did I. Perhaps it's a good idea you also you investigate your behavior saying "your question title is wrong", the fact is nothing wrong presenting the concrete example and definition. It's simple and clear "endomorphism-monoid" in your answer or identiy funciton tihng is out of topic here.
  
  – user11239932
  Mar 22 at 0:33
  

  
  
  
  

 | 
show 2 more comments

Monoid Laws

identity law:
combine (identity, a) == combine (a, identity)

associativity law:
combine (a, combine (b, c)) == combine (combine (a, b), c)

We can implement an identity element (identity) and binary operation (combine) for functions -

// identity element
const identity =
 x => x

// binary operation
const combine = (a, b) =>
 x => a (b (x))
 
// sample functions
const a =
 x => x + 3
 
const b =
 x => x - 1

const c =
 x => x * x

// uphold laws
console.log
 ( combine (identity, a) (2) === combine (a, identity) (2)
 , combine (a, combine (b, c)) (2) === combine (combine (a, b), c) (2)
 )
 
// => true
// => true

The binary operation and identity element is different depending on your domain. See the table on Wikipedia for more insight on how to implement the identity element and binary operation for various sets.

Of course you are not limited to those domains. Your custom type may have various binary operations and identity elements that satisfy the monoid laws. If the laws are upheld, your type belongs to the monoid category.

share|improve this answer

answered Mar 21 at 23:00

user633183user633183

71.9k21143184

// identity element
const identity =
 x => x

// binary operation
const combine = (a, b) =>
 x => a (b (x))
 
// sample functions
const a =
 x => x + 3
 
const b =
 x => x - 1

const c =
 x => x * x

// uphold laws
console.log
 ( combine (identity, a) (2) === combine (a, identity) (2)
 , combine (a, combine (b, c)) (2) === combine (combine (a, b), c) (2)
 )
 
// => true
// => true

// identity element
const identity =
 x => x

// binary operation
const combine = (a, b) =>
 x => a (b (x))
 
// sample functions
const a =
 x => x + 3
 
const b =
 x => x - 1

const c =
 x => x * x

// uphold laws
console.log
 ( combine (identity, a) (2) === combine (a, identity) (2)
 , combine (a, combine (b, c)) (2) === combine (combine (a, b), c) (2)
 )
 
// => true
// => true

// identity element
const identity =
 x => x

// binary operation
const combine = (a, b) =>
 x => a (b (x))
 
// sample functions
const a =
 x => x + 3
 
const b =
 x => x - 1

const c =
 x => x * x

// uphold laws
console.log
 ( combine (identity, a) (2) === combine (a, identity) (2)
 , combine (a, combine (b, c)) (2) === combine (combine (a, b), c) (2)
 )
 
// => true
// => true

share|improve this answer

answered Mar 21 at 23:00

user633183user633183

71.9k21143184

answered Mar 21 at 23:00

user633183user633183

71.9k21143184

answered Mar 21 at 23:00

user633183user633183

71.9k21143184

1

It's important to know that being able to combine things doesn't necessarily mean they are a monoid. For something to be a Monoid, it must have associativity, left identity, and right identity.

C#:

public static Func<Guid, int> Combine(
 Func<Guid, int> f,
 Func<Guid, int> g)

 return x => f(x) + g(x);

JS:

function combine(f,g) 
 return x => f(x) + g(x)


function addOne(x) 
 return x + 1;


function addTwo(x) 
 return x + 2;


let newFunction = combine(addOne, addTwo);
let result = newFunction(0);
console.log(result)

share|improve this answer

edited Mar 21 at 23:28

answered Mar 21 at 21:50

Nick AcostaNick Acosta

1,6361019

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks, I probably should ask not just combine operation since this does not make sense at least, and yes it would generate a error. Small working code please in S.O.Snippet.
  
  – user11239932
  Mar 21 at 21:55
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  combine is a function that accepts two arguments, these arguments are assumed to be functions in this case. combine will actually return a new function that takes one argument. Inside this new function, each argument, f and g will be applied to x and their results will be added together. I hope this make it easier to understand.
  
  – Nick Acosta
  Mar 21 at 23:21
  
  

  
  
  
  

add a comment | 

1

It's important to know that being able to combine things doesn't necessarily mean they are a monoid. For something to be a Monoid, it must have associativity, left identity, and right identity.

C#:

public static Func<Guid, int> Combine(
 Func<Guid, int> f,
 Func<Guid, int> g)

 return x => f(x) + g(x);

JS:

function combine(f,g) 
 return x => f(x) + g(x)


function addOne(x) 
 return x + 1;


function addTwo(x) 
 return x + 2;


let newFunction = combine(addOne, addTwo);
let result = newFunction(0);
console.log(result)

share|improve this answer

edited Mar 21 at 23:28

answered Mar 21 at 21:50

Nick AcostaNick Acosta

1,6361019

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Thanks, I probably should ask not just combine operation since this does not make sense at least, and yes it would generate a error. Small working code please in S.O.Snippet.
  
  – user11239932
  Mar 21 at 21:55
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  combine is a function that accepts two arguments, these arguments are assumed to be functions in this case. combine will actually return a new function that takes one argument. Inside this new function, each argument, f and g will be applied to x and their results will be added together. I hope this make it easier to understand.
  
  – Nick Acosta
  Mar 21 at 23:21
  
  

  
  
  
  

add a comment | 

It's important to know that being able to combine things doesn't necessarily mean they are a monoid. For something to be a Monoid, it must have associativity, left identity, and right identity.

C#:

public static Func<Guid, int> Combine(
 Func<Guid, int> f,
 Func<Guid, int> g)

 return x => f(x) + g(x);

JS:

function combine(f,g) 
 return x => f(x) + g(x)


function addOne(x) 
 return x + 1;


function addTwo(x) 
 return x + 2;


let newFunction = combine(addOne, addTwo);
let result = newFunction(0);
console.log(result)

share|improve this answer

edited Mar 21 at 23:28

answered Mar 21 at 21:50

Nick AcostaNick Acosta

1,6361019

public static Func<Guid, int> Combine(
 Func<Guid, int> f,
 Func<Guid, int> g)

 return x => f(x) + g(x);

function combine(f,g) 
 return x => f(x) + g(x)


function addOne(x) 
 return x + 1;


function addTwo(x) 
 return x + 2;


let newFunction = combine(addOne, addTwo);
let result = newFunction(0);
console.log(result)

function combine(f,g) 
 return x => f(x) + g(x)


function addOne(x) 
 return x + 1;


function addTwo(x) 
 return x + 2;


let newFunction = combine(addOne, addTwo);
let result = newFunction(0);
console.log(result)

function combine(f,g) 
 return x => f(x) + g(x)


function addOne(x) 
 return x + 1;


function addTwo(x) 
 return x + 2;


let newFunction = combine(addOne, addTwo);
let result = newFunction(0);
console.log(result)

share|improve this answer

edited Mar 21 at 23:28

answered Mar 21 at 21:50

Nick AcostaNick Acosta

1,6361019

answered Mar 21 at 21:50

Nick AcostaNick Acosta

1,6361019

answered Mar 21 at 21:50

Nick AcostaNick Acosta

1,6361019