I'm writing a introductory JavaScript tutorial series, I have a question about terminology.

When explaining the Array.prototype methods, I've given an example of some code like:

const letters = ['a', 'b', 'c']; 
letters.forEach((value) => {
    console.log("the value is: " + value)
}); 

I've said what's happening here is:

1. Firstly, we're calling an object function (a function that belongs to and object, in this case the object is the letters array).
2. We pass as the first and only argument, a function: (value) => {//...} This is commonly known as a lambda or anonymous function.. (Unfortunately AWS Lambda functions, which is a service provided by Amazon confuses the terminology a bit 😭 )
3. That function has a parameter value, that is is going to be the current element as the we iterate over the array.
4. We print the value.

So the first question is, say instead my code looked like:

function printCurrentValue(value) {
    console.log("the value is: " + value)
}

const letters = ['a', 'b', 'c']; 
letters.forEach(printCurrentValue); 

• Would we still call that an anonymous function? After all, it it is now assigned to a variable.
• Would we still call it a lambda function?

That is - intuitively I would say an anonymous function is any unnamed function, whereas I would still want to say that a named function can be used as a lambda function, as would be the case here, because lambda function, if you'll excuse my vagueness, is a 'a function that produces one value from another or something', I'm sure there's a better definition.

Elsewhere in the tutorial, I want to talk about callbacks.

For example, I might have some code like:

fetch('/user')
.then((res) => res.json())
.then((json) => console.log(json)); 

Where (res) => res.json() and (json) => console.log(json) are callbacks and they are also anonymous functions - but I'm not sure it's correct to call them lambda functions.

That is, I would define a callback as 'a function that is called else where in your application'. By that definition, the lambda functions passed into an Array.prototype method are callback functions.

Is there a tidy way to differentiate between the three terms?

I'm writing a introductory JavaScript tutorial series, I have a question about terminology.

When explaining the Array.prototype methods, I've given an example of some code like:

const letters = ['a', 'b', 'c']; 
letters.forEach((value) => {
    console.log("the value is: " + value)
}); 

I've said what's happening here is:

1. Firstly, we're calling an object function (a function that belongs to an object, in this case the object is the letters array).
2. We pass as the first and only argument, a function: (value) => {//...} This is commonly known as a lambda or anonymous function.. (Unfortunately AWS Lambda functions, which is a service provided by Amazon confuses the terminology a bit 😭 )
3. That function has a parameter value, that is is going to be the current element as the we iterate over the array.
4. We print the value.

So the first question is, say instead my code looked like:

function printCurrentValue(value) {
    console.log("the value is: " + value)
}

const letters = ['a', 'b', 'c']; 
letters.forEach(printCurrentValue); 

• Would we still call that an anonymous function? After all, it it is now assigned to a variable.
• Would we still call it a lambda function?

That is - intuitively I would say an anonymous function is any unnamed function, whereas I would still want to say that a named function can be used as a lambda function, as would be the case here, because lambda function, if you'll excuse my vagueness, is a 'a function that produces one value from another or something', I'm sure there's a better definition.

Elsewhere in the tutorial, I want to talk about callbacks.

For example, I might have some code like:

fetch('/user')
.then((res) => res.json())
.then((json) => console.log(json)); 

Where (res) => res.json() and (json) => console.log(json) are callbacks and they are also anonymous functions - but I'm not sure it's correct to call them lambda functions.

That is, I would define a callback as 'a function that is called else where in your application'. By that definition, the lambda functions passed into an Array.prototype method are callback functions.

Is there a tidy way to differentiate between the three terms?