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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Purely functional programming</span></span>

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<p>In <a href="Computer_science" title="Computer science">computer science</a>, <b>purely functional programming</b> usually designates a <a href="Programming_paradigm" title="Programming paradigm">programming paradigm</a>—a style of building the structure and elements of computer programs—that treats all <a href="Computation" title="Computation">computation</a> as the evaluation of <a href="Function_(mathematics)" title="Function (mathematics)">mathematical functions</a>.

</p><p><a href="Program_state" class="mw-redirect" title="Program state">Program state</a> and <a href="Mutable" class="mw-redirect" title="Mutable">mutable</a> objects are usually modeled with <a href="Temporal_logic" title="Temporal logic">temporal logic</a>, as explicit variables that represent the program state at each step of a program execution: a variable state is passed as an <a href="Input_parameter" class="mw-redirect" title="Input parameter">input parameter</a> of a state-transforming function, which returns the updated state as part of its return value. This style handles state changes without losing the <a href="Referential_transparency" title="Referential transparency">referential transparency</a> of the program expressions.

</p><p>Purely functional programming consists of ensuring that functions, inside the <a href="Functional_programming" title="Functional programming">functional</a> paradigm, will only depend on their arguments, regardless of any global or local state. A pure functional subroutine only has visibility of changes of state represented by state variables included in its scope.

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<div class="mw-heading mw-heading2"><h2 id="Difference_between_pure_and_impure_functional_programming">Difference between pure and impure functional programming</h2></div>

<p>The exact difference between pure and impure functional programming is a matter of controversy. Sabry's proposed definition of purity is that all common <a href="Evaluation_strategy" title="Evaluation strategy">evaluation strategies</a> (call-by-name, call-by-value, and call-by-need) produce the same result, ignoring strategies that error or diverge.<sup id="cite_ref-Sabry_1-0" class="reference"><a href="#cite_note-Sabry-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>

</p><p>A program is usually said to be functional when it uses some concepts of <a href="Functional_programming" title="Functional programming">functional programming</a>, such as <a href="First-class_function" title="First-class function">first-class functions</a> and <a href="Higher-order_function" title="Higher-order function">higher-order functions</a>.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> However, a first-class function need not be purely functional, as it may use techniques from the <a href="Imperative_programming" title="Imperative programming">imperative</a> paradigm, such as <a href="Array_data_structure" class="mw-redirect" title="Array data structure">arrays</a> or input/output <a href="Method_(computer_programming)" title="Method (computer programming)">methods</a> that use mutable cells, which update their state as side effects. In fact, the earliest programming languages cited as being functional, <a href="Information_Processing_Language" title="Information Processing Language">IPL</a> and <a href="Lisp_(programming_language)" title="Lisp (programming language)">Lisp</a>,<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> are both "impure" functional languages by Sabry's definition.

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<div class="mw-heading mw-heading2"><h2 id="Properties_of_purely_functional_programming">Properties of purely functional programming</h2></div>

<div class="mw-heading mw-heading3"><h3 id="Strict_versus_non-strict_evaluation">Strict versus non-strict evaluation</h3></div>

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</style><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="Evaluation_strategy" title="Evaluation strategy">Evaluation strategy</a></div>

<p>Each <a href="Evaluation_strategy" title="Evaluation strategy">evaluation strategy</a> which ends on a purely functional program returns the same result. In particular, it ensures that the programmer does not have to consider in which order programs are evaluated, since <a href="Eager_evaluation" class="mw-redirect" title="Eager evaluation">eager evaluation</a> will return the same result as <a href="Lazy_evaluation" title="Lazy evaluation">lazy evaluation</a>. However, it is still possible that an eager evaluation may not terminate while the lazy evaluation of the same program halts.

An advantage of this is that lazy evaluation can be implemented much more easily; as all expressions will return the same result at any moment (regardless of program state), their evaluation can be delayed as much as necessary.

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<div class="mw-heading mw-heading3"><h3 id="Parallel_computing">Parallel computing</h3></div>

<p>In a purely functional language, the only dependencies between computations are data dependencies, and computations are deterministic. Therefore, to program in parallel, the programmer need only specify the pieces that should be computed in parallel, and the runtime can handle all other details such as distributing tasks to processors, managing synchronization and communication, and collecting garbage in parallel. This style of programming avoids common issues such as race conditions and deadlocks, but has less control than an imperative language.<sup id="cite_ref-Marlow_5-0" class="reference"><a href="#cite_note-Marlow-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup>

</p><p>To ensure a speedup, the granularity of tasks must be carefully chosen to be neither too big nor too small. In theory, it is possible to use runtime profiling and compile-time analysis to judge whether introducing parallelism will speed up the program, and thus automatically parallelize purely functional programs. In practice, this has not been terribly successful, and fully automatic parallelization is not practical.<sup id="cite_ref-Marlow_5-1" class="reference"><a href="#cite_note-Marlow-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup>

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<div class="mw-heading mw-heading3"><h3 id="Data_structures">Data structures</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Main article: <a href="Purely_functional_data_structure" title="Purely functional data structure">Purely functional data structure</a></div>

<p><a href="Purely_functional_data_structure" title="Purely functional data structure">Purely functional data structures</a> are <a href="Persistent_data_structure" title="Persistent data structure">persistent</a>. Persistency is required for functional programming; without it, the same computation could return different results. Functional programming may use persistent non-purely functional <a href="Data_structure" title="Data structure">data structures</a>, while those data structures may not be used in purely functional programs.

</p><p>Purely functional <a href="Data_structure" title="Data structure">data structures</a> are often represented in a different way than their <a href="Imperative_programming" title="Imperative programming">imperative</a> counterparts.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> For example, <a href="Array_data_structure" class="mw-redirect" title="Array data structure">array</a> with constant-time access and update is a basic component of most imperative languages and many imperative data-structures, such as <a href="Hash_table" title="Hash table">hash table</a> and <a href="Binary_heap" title="Binary heap">binary heap</a>, are based on arrays. Arrays can be replaced by <a href="Map_(computer_science)" class="mw-redirect" title="Map (computer science)">map</a> or random access list, which admits purely functional implementation, but the access and update time is <a href="Logarithm" title="Logarithm">logarithmic</a>. Therefore, purely functional data structures can be used in languages which are non-functional, but they may not be the most efficient tool available, especially if persistency is not required.

</p><p>In general, conversion of an imperative program to a purely functional one also requires ensuring that the formerly-mutable structures are now explicitly returned from functions that update them, a program structure called <a href="Store-passing_style" title="Store-passing style">store-passing style</a>.

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<div class="mw-heading mw-heading2"><h2 id="Purely_functional_language">Purely functional language</h2></div>

<div role="note" class="hatnote navigation-not-searchable">For a more comprehensive list, see <a href="List_of_programming_languages_by_type#Pure" title="List of programming languages by type">List of programming languages by type § Pure</a>.</div>

<p>A purely functional language is a language which only admits purely functional programming. Purely functional programs can however be written in languages which are not purely functional.

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<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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</style><cite id="CITEREFSabry1993" class="citation journal cs1">Sabry, Amr (January 1993). "What is a purely functional language?". <i>Journal of Functional Programming</i>. <b>8</b> (1): <span class="nowrap">1–</span>22. <a href="CiteSeerX_(identifier)" class="mw-redirect" title="CiteSeerX (identifier)">CiteSeerX</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.27.7800">10.1.1.27.7800</a></span>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1017%2FS0956796897002943">10.1017/S0956796897002943</a>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:30595712">30595712</a>.</cite></span>

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<li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><cite id="CITEREFAtencio2016" class="citation book cs1">Atencio, Luis (18 June 2016). <i>Functional Programming in Javascript</i>. Manning Publications. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-1617292828</bdi>.</cite></span>

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<li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text">The memoir of <a href="Herbert_A._Simon" title="Herbert A. Simon">Herbert A. Simon</a> (1991), <i>Models of My Life</i> pp.189-190 <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-465-04640-1</bdi> claims that he, Al Newell, and Cliff Shaw are "commonly adjudged to be the parents of [the] artificial intelligence [field]", for writing <a href="Logic_Theorist" title="Logic Theorist">Logic Theorist</a>, a program which proved theorems from <i><a href="Principia_Mathematica" title="Principia Mathematica">Principia Mathematica</a></i> automatically. In order to accomplish this, they had to invent a language and a paradigm which, which viewed retrospectively, embeds functional programming.</span>

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<li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><cite id="CITEREFMcCarthy1978" class="citation book cs1"><a href="John_McCarthy_(computer_scientist)" title="John McCarthy (computer scientist)">McCarthy, John</a> (June 1978). <span class="id-lock-subscription" title="Paid subscription required"><a rel="nofollow" class="external text" href="http://citeseer.ist.psu.edu/mccarthy78history.html">"History of LISP"</a></span>. <i>The first ACM SIGPLAN conference on History of programming languages - HOPL-1</i>. pp. <span class="nowrap">217–</span>223. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1145%2F800025.808387">10.1145/800025.808387</a>.</cite></span>

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<li id="cite_note-Marlow-5"><span class="mw-cite-backlink">^ <a href="#cite_ref-Marlow_5-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Marlow_5-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><cite id="CITEREFMarlow2013" class="citation book cs1">Marlow, Simon (18 June 2013). <i>Parallel and Concurrent Programming in Haskell: Techniques for Multicore and Multithreaded Programming</i>. O'Reilly Media. pp. <span class="nowrap">5–</span>6. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-1449335946</bdi>.</cite></span>

</li>

<li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://www.cambridge.org/us/academic/subjects/computer-science/algorithmics-complexity-computer-algebra-and-computational-g/purely-functional-data-structures"><i>Purely functional data structures</i></a> by <a href="Chris_Okasaki" title="Chris Okasaki">Chris Okasaki</a>, <a href="Cambridge_University_Press" title="Cambridge University Press">Cambridge University Press</a>, 1998, <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-521-66350-4</bdi></span>

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</style><div id="Programming_paradigms_(Comparison_by_language)368" style="font-size:114%;margin:0 4em"><a href="Programming_paradigm" title="Programming paradigm">Programming paradigms</a> (<a href="Comparison_of_multi-paradigm_programming_languages" title="Comparison of multi-paradigm programming languages">Comparison by language</a>)</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Imperative_programming" title="Imperative programming">Imperative</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Structured_programming" title="Structured programming">Structured</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Jackson_structured_programming" title="Jackson structured programming">Jackson structures</a></li>

<li><a href="Block_(programming)" title="Block (programming)">Block-structured</a></li>

<li><a href="Modular_programming" title="Modular programming">Modular</a></li>

<li><a href="Non-structured_programming" title="Non-structured programming">Non-structured</a></li>

<li><a href="Procedural_programming" title="Procedural programming">Procedural</a></li>

<li><a href="Programming_in_the_large_and_programming_in_the_small" title="Programming in the large and programming in the small">Programming in the large and in the small</a></li>

<li><a href="Design_by_contract" title="Design by contract">Design by contract</a></li>

<li><a href="Invariant-based_programming" title="Invariant-based programming">Invariant-based</a></li>

<li><a href="Nested_function" title="Nested function">Nested function</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Object-oriented_programming" title="Object-oriented programming">Object-oriented</a><br>(<a href="Comparison_of_programming_languages_(object-oriented_programming)" title="Comparison of programming languages (object-oriented programming)">comparison</a>, <a href="List_of_object-oriented_programming_languages" title="List of object-oriented programming languages">list</a>)</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Class-based_programming" title="Class-based programming">Class-based</a>, <a href="Prototype-based_programming" title="Prototype-based programming">Prototype-based</a>, <a href="Object-based_language" title="Object-based language">Object-based</a></li>

<li><a href="Agent-oriented_programming" title="Agent-oriented programming">Agent</a></li>

<li><a href="Immutable_object" title="Immutable object">Immutable object</a></li>

<li><a href="Persistent_programming_language" title="Persistent programming language">Persistent</a></li>

<li><a href="Uniform_function_call_syntax" title="Uniform function call syntax">Uniform function call syntax</a></li></ul>

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Declarative_programming" title="Declarative programming">Declarative</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Functional_programming" title="Functional programming">Functional</a><br>(<a href="Comparison_of_functional_programming_languages" title="Comparison of functional programming languages">comparison</a>)</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Recursion_(computer_science)" title="Recursion (computer science)">Recursive</a></li>

<li><a href="Anonymous_function" title="Anonymous function">Anonymous function</a> (<a href="Partial_application" title="Partial application">Partial application</a>)</li>

<li><a href="Higher-order_programming" title="Higher-order programming">Higher-order</a></li>

<li><a href="Total_functional_programming" title="Total functional programming">Total</a></li>

<li><a href="Strict_programming_language" title="Strict programming language">Strict</a></li>

<li><a href="Generalized_algebraic_data_type" title="Generalized algebraic data type">GADTs</a></li>

<li><a href="Dependent_type" title="Dependent type">Dependent types</a></li>

<li><a href="Functional_logic_programming" title="Functional logic programming">Functional logic</a></li>

<li><a href="Tacit_programming" title="Tacit programming">Point-free style</a></li>

<li><a href="Expression-oriented_programming_language" title="Expression-oriented programming language">Expression-oriented</a></li>

<li><a href="Applicative_programming_language" title="Applicative programming language">Applicative</a>, <a href="Concatenative_programming_language" title="Concatenative programming language">Concatenative</a></li>

<li><a href="Function-level_programming" title="Function-level programming">Function-level</a>, <a href="Value-level_programming" title="Value-level programming">Value-level</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Dataflow_programming" title="Dataflow programming">Dataflow</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Flow-based_programming" title="Flow-based programming">Flow-based</a></li>

<li><a href="Reactive_programming" title="Reactive programming">Reactive</a> (<a href="Functional_reactive_programming" title="Functional reactive programming">Functional reactive</a>)</li>

<li><a href="Signal_programming" class="mw-redirect" title="Signal programming">Signals</a></li>

<li><a href="Stream_processing" title="Stream processing">Streams</a></li>

<li><a href="Synchronous_programming_language" title="Synchronous programming language">Synchronous</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Logic_programming" title="Logic programming">Logic</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Abductive_logic_programming" title="Abductive logic programming">Abductive logic</a></li>

<li><a href="Answer_set_programming" title="Answer set programming">Answer set</a></li>

<li><a href="Constraint_programming" title="Constraint programming">Constraint</a> (<a href="Constraint_logic_programming" title="Constraint logic programming">Constraint logic</a>)</li>

<li><a href="Inductive_logic_programming" title="Inductive logic programming">Inductive logic</a></li>

<li><a href="Nondeterministic_programming" title="Nondeterministic programming">Nondeterministic</a></li>

<li><a href="Ontology_language" title="Ontology language">Ontology</a></li>

<li><a href="Probabilistic_logic_programming" title="Probabilistic logic programming">Probabilistic logic</a></li>

<li><a href="Query_language" title="Query language">Query</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Domain-specific_language" title="Domain-specific language">DSL</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Algebraic_modeling_language" title="Algebraic modeling language">Algebraic modeling</a></li>

<li><a href="Array_programming" title="Array programming">Array</a></li>

<li><a href="Automata-based_programming" title="Automata-based programming">Automata-based</a> (<a href="Action_language" title="Action language">Action</a>)</li>

<li><a href="Command_language" title="Command language">Command</a> (<a href="Spacecraft_command_language" title="Spacecraft command language">Spacecraft</a>)</li>

<li><a href="Differentiable_programming" title="Differentiable programming">Differentiable</a></li>

<li><a href="Grammar-oriented_programming" title="Grammar-oriented programming">Grammar-oriented</a></li>

<li><a href="Interface_description_language" title="Interface description language">Interface description</a></li>

<li><a href="Language-oriented_programming" title="Language-oriented programming">Language-oriented</a></li>

<li><a href="List_comprehension" title="List comprehension">List comprehension</a></li>

<li><a href="Modeling_language" title="Modeling language">Modeling</a></li>

<li><a href="Natural-language_programming" class="mw-redirect" title="Natural-language programming">Natural language</a></li>

<li><a href="Non-English-based_programming_languages" title="Non-English-based programming languages">Non-English-based</a></li>

<li><a href="Page_description_language" title="Page description language">Page description</a></li>

<li><a href="Pipeline_(software)" title="Pipeline (software)">Pipes</a> and <a href="Filter_(software)" title="Filter (software)">filters</a></li>

<li><a href="Probabilistic_programming" title="Probabilistic programming">Probabilistic</a></li>

<li><a href="Quantum_programming" title="Quantum programming">Quantum</a></li>

<li><a href="Scientific_programming_language" title="Scientific programming language">Scientific</a></li>

<li><a href="Scripting_language" title="Scripting language">Scripting</a></li>

<li><a href="Set_theoretic_programming" title="Set theoretic programming">Set-theoretic</a></li>

<li><a href="Simulation_language" title="Simulation language">Simulation</a></li>

<li><a href="Stack-oriented_programming" title="Stack-oriented programming">Stack-based</a></li>

<li><a href="System_programming_language" title="System programming language">System</a></li>

<li><a href="Tactile_programming_language" title="Tactile programming language">Tactile</a></li>

<li><a href="Template_processor" title="Template processor">Templating</a></li>

<li><a href="Transformation_language" title="Transformation language">Transformation</a> (<a href="Graph_rewriting" title="Graph rewriting">Graph rewriting</a>, <a href="Production_system_(computer_science)" title="Production system (computer science)">Production</a>, <a href="Pattern_matching" title="Pattern matching">Pattern</a>)</li>

<li><a href="Visual_programming_language" title="Visual programming language">Visual</a></li></ul>

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Concurrent_computing" title="Concurrent computing">Concurrent</a>,<br><a href="Distributed_computing" title="Distributed computing">distributed</a>,<br><a href="Parallel_computing" title="Parallel computing">parallel</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Actor_model" title="Actor model">Actor-based</a></li>

<li><a href="Automatic_mutual_exclusion" title="Automatic mutual exclusion">Automatic mutual exclusion</a></li>

<li><a href="Choreographic_programming" title="Choreographic programming">Choreographic programming</a></li>

<li><a href="Concurrent_logic_programming" title="Concurrent logic programming">Concurrent logic</a> (<a href="Concurrent_constraint_logic_programming" title="Concurrent constraint logic programming">Concurrent constraint logic</a>)</li>

<li><a href="Concurrent_object-oriented_programming" title="Concurrent object-oriented programming">Concurrent OO</a></li>

<li><a href="Macroprogramming" title="Macroprogramming">Macroprogramming</a></li>

<li><a href="Multitier_programming" title="Multitier programming">Multitier programming</a></li>

<li><a href="Organic_computing" title="Organic computing">Organic computing</a></li>

<li><a href="Parallel_programming_model" title="Parallel programming model">Parallel programming models</a></li>

<li><a href="Partitioned_global_address_space" title="Partitioned global address space">Partitioned global address space</a></li>

<li><a href="Process-oriented_programming" title="Process-oriented programming">Process-oriented</a></li>

<li><a href="Relativistic_programming" title="Relativistic programming">Relativistic programming</a></li>

<li><a href="Service-oriented_programming" title="Service-oriented programming">Service-oriented</a></li>

<li><a href="Structured_concurrency" title="Structured concurrency">Structured concurrency</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Metaprogramming" title="Metaprogramming">Metaprogramming</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Attribute-oriented_programming" title="Attribute-oriented programming">Attribute-oriented</a></li>

<li><a href="Automatic_programming" title="Automatic programming">Automatic</a> (<a href="Inductive_programming" title="Inductive programming">Inductive</a>)</li>

<li><a href="Dynamic_programming_language" title="Dynamic programming language">Dynamic</a></li>

<li><a href="Extensible_programming" title="Extensible programming">Extensible</a></li>

<li><a href="Generic_programming" title="Generic programming">Generic</a></li>

<li><a href="Homoiconicity" title="Homoiconicity">Homoiconicity</a></li>

<li><a href="Interactive_programming" title="Interactive programming">Interactive</a></li>

<li><a href="Macro_(computer_science)" title="Macro (computer science)">Macro</a> (<a href="Hygienic_macro" title="Hygienic macro">Hygienic</a>)</li>

<li><a href="Metalinguistic_abstraction" title="Metalinguistic abstraction">Metalinguistic abstraction</a></li>

<li><a href="Multi-stage_programming" title="Multi-stage programming">Multi-stage</a></li>

<li><a href="Program_synthesis" title="Program synthesis">Program synthesis</a> (<a href="Bayesian_program_synthesis" title="Bayesian program synthesis">Bayesian</a>, <a href="Inferential_programming" title="Inferential programming">Inferential</a>, <a href="Programming_by_demonstration" title="Programming by demonstration">by demonstration</a>, <a href="Programming_by_example" title="Programming by example">by example</a>)</li>

<li><a href="Reflective_programming" title="Reflective programming">Reflective</a></li>

<li><a href="Self-modifying_code" title="Self-modifying code">Self-modifying code</a></li>

<li><a href="Symbolic_programming" title="Symbolic programming">Symbolic</a></li>

<li><a href="Template_metaprogramming" title="Template metaprogramming">Template</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Separation_of_concerns" title="Separation of concerns">Separation<br>of concerns</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Aspect-oriented_programming" title="Aspect-oriented programming">Aspects</a></li>

<li><a href="Component-based_software_engineering" title="Component-based software engineering">Components</a></li>

<li><a href="Data-driven_programming" title="Data-driven programming">Data-driven</a></li>

<li><a href="Data-oriented_design" title="Data-oriented design">Data-oriented</a></li>

<li><a href="Event-driven_programming" title="Event-driven programming">Event-driven</a></li>

<li><a href="Feature-oriented_programming" title="Feature-oriented programming">Features</a></li>

<li><a href="Literate_programming" title="Literate programming">Literate</a></li>

<li><a href="Role-oriented_programming" title="Role-oriented programming">Roles</a></li>

<li><a href="Subject-oriented_programming" title="Subject-oriented programming">Subjects</a></li></ul>

</div></td></tr></tbody></table></div>

<div class="navbox-styles"></div><div role="navigation" class="navbox" aria-labelledby="Types_of_programming_languages107" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Types_of_programming_languages107" style="font-size:114%;margin:0 4em"><a href="Programming_paradigm" title="Programming paradigm">Types of programming languages</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Level</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Machine_code" title="Machine code">Machine</a></li>

<li><a href="Assembly_language" title="Assembly language">Assembly</a></li>

<li><a href="Compiled_language" title="Compiled language">Compiled</a></li>

<li><a href="Interpreted_language" class="mw-redirect" title="Interpreted language">Interpreted</a></li></ul>

<ul><li><a href="Low-level_programming_language" title="Low-level programming language">Low-level</a></li>

<li><a href="High-level_programming_language" title="High-level programming language">High-level</a></li>

<li><a href="Very_high-level_programming_language" title="Very high-level programming language">Very high-level</a></li>

<li><a href="Esoteric_programming_language" title="Esoteric programming language">Esoteric</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Programming_language_generations" title="Programming language generations">Generation</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="First-generation_programming_language" title="First-generation programming language">First</a></li>

<li><a href="Second-generation_programming_language" title="Second-generation programming language">Second</a></li>

<li><a href="Third-generation_programming_language" title="Third-generation programming language">Third</a></li>

<li><a href="Fourth-generation_programming_language" title="Fourth-generation programming language">Fourth</a></li>

<li><a href="Fifth-generation_programming_language" title="Fifth-generation programming language">Fifth</a></li></ul>

</div></td></tr></tbody></table></div></div><div><div class="zim-footer">

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