A particular challenge is related to the support of higher-order functions, also known as the Funarg problem.

It would use a higher-order function that takes as arguments a function and a list.

In mathematics higher-order functions are also known as operators or functionals.

Higher-order functions are rarely used in older imperative programming.

The concepts of curried and higher-order functions are clearly useful in mathematical programs.

This higher-order function is typically named filter in functional programming languages.

Curried and higher-order functions can be used to eliminate redundant code.

Graham Hutton also used higher-order functions for basic parsing in 1992.

This means it cannot be used in higher-order functions; it is second-class.

The function, found in many functional programming languages, is one example of a higher-order function.

Both method and block are higher-order functions.

The Common Lisp library relies heavily on such higher-order functions.

Since Haskell supports higher-order functions, functions can be passed as arguments.

Emphasis on recursion and higher-order functions instead of side-effect-based looping.

In object-oriented programming languages that do not support higher-order functions, objects can be an effective substitute.

Other binding operators, like the summation sign, can be thought of as higher-order functions applying to a function.

In this Scheme example the higher-order function g() takes a number and returns a function.

The mushroom bodies in insects are a paired structure that are critical for higher-order functions.

In functional programming and lambda calculus, function types are used to express the idea of higher-order functions.

For example, the message select: on a Collection is equivalent to the higher-order function filter on an appropriate functor.

In functional programming languages, function composition can be naturally expressed as a higher-order function or operator.

First-class functions are a necessity for the functional programming style, in which the use of higher-order functions is a standard practice.

The data part of the toolset is based on abstract equational data types extended with higher-order functions.

D supports functional programming features such as function literals, closures, and the use of higher-order functions.

Because fixed-point combinators are higher-order functions, their history is intimately related to the development of lambda calculus.