Editing Function-level programming (section)

{{redirect|function-level|the term in mental health assessments|Global Assessment of Functioning}}
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In computer science, '''function-level''' programming refers to one of the two contrasting [[programming paradigm]]s identified by [[John Backus]] in his work on programs as mathematical objects, the other being [[value-level programming]].

In his 1977 [[Turing Award]] lecture, Backus set forth what he considered to be the need to switch to a different philosophy in programming language design:<ref>{{cite journal|doi=10.1145/359576.359579|title=Can programming be liberated from the von Neumann style?: A functional style and its algebra of programs|journal=Communications of the ACM|volume=21|issue=8|pages=613–641|year=1978|last1=Backus|first1=John|url=https://www.cs.ucf.edu/~dcm/Teaching/COT4810-Fall%202012/Literature/Backus.pdf|doi-access=free}}</ref>
<blockquote>Programming languages appear to be in trouble. Each successive language incorporates, with a little cleaning up, all the features of its predecessors plus a few more. [...] Each new language claims new and fashionable features... but the plain fact is that few languages make programming sufficiently cheaper or more reliable to justify the cost of producing and learning to use them.</blockquote>

He designed [[FP (programming language)|FP]] to be the first [[programming language]] to specifically support the function-level programming style.

A ''function-level'' program is '''variable-free''' (cf. [[point-free programming|''point-free'' programming]]), since [[Variable (programming)|program variable]]s, which are essential in value-level definitions, are not needed in function-level programs.