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While loop

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</style><table class="sidebar nomobile nowraplinks"><tbody><tr><th class="sidebar-title"><a href="Control_flow#Loops" title="Control flow">Loop constructs</a></th></tr><tr><td class="sidebar-content">

<ul><li><a href="Do_while_loop" title="Do while loop">Do while loop</a></li>

<li><a href="Foreach_loop" title="Foreach loop">Foreach loop</a></li>

<li><a href="Infinite_loop" title="Infinite loop">Infinite loop</a></li>

<li><a href="Control_flow" title="Control flow">Control flow</a></li></ul>

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In most computer <a href="Programming_language" title="Programming language">programming languages</a>, a while loop is a <a href="Control_flow" title="Control flow">control flow</a> <a href="Statement_(computer_science)" title="Statement (computer science)">statement</a> that allows code to be executed repeatedly based on a given <a href="Boolean_data_type" title="Boolean data type">Boolean</a> condition. The while loop can be thought of as a repeating <a href="Conditional_(computer_programming)" title="Conditional (computer programming)">if statement</a>.

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

The while construct consists of a block of code and a condition/expression.<a href="#cite_note-:0-1">[1]</a> The condition/expression is evaluated, and if the condition/expression is true,<a href="#cite_note-:0-1">[1]</a> the code within all of their following in the block is executed. This repeats until the condition/expression becomes <a href="False_(logic)" title="False (logic)">false</a>. Because the while loop checks the condition/expression before the block is executed, the control structure is often also known as a pre-test loop. Compare this with the <a href="Do_while_loop" title="Do while loop">do while loop</a>, which tests the condition/expression after the loop has executed.

For example, in the languages <a href="C_(programming_language)" title="C (programming language)">C</a>, <a href="Java_(programming_language)" title="Java (programming language)">Java</a>, <a href="C_Sharp_(programming_language)" title="C Sharp (programming language)">C#</a>,<a href="#cite_note-2">[2]</a> <a href="Objective-C" title="Objective-C">Objective-C</a>, and <a href="C%2B%2B" title="C++">C++</a>, (which <a href="Polyglot_(computing)" title="Polyglot (computing)">use the same syntax</a> in this case), the code fragment

<div class="mw-highlight mw-highlight-lang-c mw-content-ltr" dir="ltr"><pre>int x = 0;

while (x < 5) {

printf ("x = %d\n", x);

x++;

}

</pre></div>

first checks whether x is less than 5, which it is, so then the {loop body} is entered, where the printf function is run and x is incremented by 1. After completing all the statements in the loop body, the condition, (x < 5), is checked again, and the loop is executed again, this process repeating until the <a href="Variable_(computer_science)" title="Variable (computer science)">variable</a> x has the value 5.

It is possible, and in some cases desirable, for the condition to always evaluate to true, creating an <a href="Infinite_loop" title="Infinite loop">infinite loop</a>. When such a loop is created intentionally, there is usually another control structure (such as a <a href="Control_flow" title="Control flow">break</a> statement) that controls termination of the loop.

For example:

<div class="mw-highlight mw-highlight-lang-c mw-content-ltr" dir="ltr"><pre>while (true) {

// do complicated stuff

if (someCondition)

break;

// more stuff

}

</pre></div>

<div class="mw-heading mw-heading2"><h2 id="Demonstrating_while_loops">Demonstrating while loops</h2></div>

These while loops will calculate the <a href="Factorial" title="Factorial">factorial</a> of the number 5:

<div class="mw-heading mw-heading3"><h3 id="ActionScript_3">ActionScript 3</h3></div>

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</style><div role="note" class="hatnote navigation-not-searchable">Further information: <a href="ActionScript_3.0" class="mw-redirect" title="ActionScript 3.0">ActionScript 3.0</a></div>

<div class="mw-highlight mw-highlight-lang-actionscript mw-content-ltr" dir="ltr"><pre>var counter: int = 5;

var factorial: int = 1;

while (counter > 1) {

factorial *= counter;

counter--;

}

Printf("Factorial = %d", factorial);

</pre></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Ada_(programming_language)" title="Ada (programming language)">Ada (programming language)</a></div>

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<div class="side-box-text plainlist">The Wikibook <a href="https://en.wikibooks.org/wiki/Ada_Programming" class="extiw external" title="wikibooks:Ada Programming">Ada_Programming</a> has a page on the topic of: <a href="https://en.wikibooks.org/wiki/Ada_Programming/Control" class="extiw external" title="wikibooks:Ada Programming/Control">Control</a></div></div>

</div>

<div class="mw-highlight mw-highlight-lang-ada mw-content-ltr" dir="ltr"><pre>with Ada.Integer_Text_IO;

procedure Factorial is

Counter : Integer := 5;

Factorial : Integer := 1;

begin

while Counter > 0 loop

Factorial := Factorial * Counter;

Counter := Counter - 1;

end loop;

Ada.Integer_Text_IO.Put (Factorial);

end Factorial;

</pre></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="APL_(programming_language)" title="APL (programming language)">APL (programming language)</a></div>

<div class="mw-highlight mw-highlight-lang-apl mw-content-ltr" dir="ltr"><pre>counter ← 5

factorial ← 1

:While counter > 0

factorial ×← counter

counter -← 1

:EndWhile

⎕ ← factorial

</pre></div>

or simply

<div class="mw-highlight mw-highlight-lang-apl mw-content-ltr" dir="ltr"><pre>!5

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="AutoHotkey">AutoHotkey</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="AutoHotkey" title="AutoHotkey">AutoHotkey</a></div>

<div class="mw-highlight mw-highlight-lang-autohotkey mw-content-ltr" dir="ltr"><pre>counter := 5

factorial := 1

While counter > 0

factorial *= counter--

MsgBox % factorial

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="Small_Basic">Small Basic</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Microsoft_Small_Basic" title="Microsoft Small Basic">Microsoft Small Basic</a></div>

<div class="mw-highlight mw-highlight-lang-vbnet mw-content-ltr" dir="ltr"><pre>counter = 5 ' Counter = 5

factorial = 1 ' initial value of variable "factorial"

While counter > 0

factorial = factorial * counter

counter = counter - 1

TextWindow.WriteLine(counter)

EndWhile

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="Visual_Basic">Visual Basic</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Visual_Basic" title="Visual Basic">Visual Basic</a></div>

<div class="mw-highlight mw-highlight-lang-vbnet mw-content-ltr" dir="ltr"><pre>Dim counter As Integer = 5 ' init variable and set value

Dim factorial As Integer = 1 ' initialize factorial variable

Do While counter > 0

Loop ' program goes here, until counter = 0

'Debug.Print factorial ' Console.WriteLine(factorial) in Visual Basic .NET

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="Bourne_(Unix)_shell">Bourne (Unix) shell</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Bourne_shell" title="Bourne shell">Bourne shell</a></div>

<div class="mw-highlight mw-highlight-lang-bash mw-content-ltr" dir="ltr"><pre>counter=5

factorial=1

while [ $counter -gt 0 ]; do

factorial=$((factorial * counter))

counter=$((counter - 1))

done

echo $factorial

</pre></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="C_(programming_language)" title="C (programming language)">C (programming language)</a> and <a href="C%2B%2B" title="C++">C++</a></div>

<div class="mw-highlight mw-highlight-lang-c mw-content-ltr" dir="ltr"><pre>int main() {

int count = 5;

int factorial = 1;

while (count > 1)

factorial *= count--;

printf("%d", factorial);

}

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="ColdFusion_Markup_Language_(CFML)">ColdFusion Markup Language (CFML)</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="ColdFusion_Markup_Language" title="ColdFusion Markup Language">ColdFusion Markup Language</a></div>

<div class="mw-heading mw-heading4"><h4 id="Script_syntax">Script syntax</h4></div>

<div class="mw-highlight mw-highlight-lang-cfs mw-content-ltr" dir="ltr"><pre>counter = 5;

factorial = 1;

while (counter > 1) {

factorial *= counter--;

}

writeOutput(factorial);

</pre></div>

<div class="mw-heading mw-heading4"><h4 id="Tag_syntax">Tag syntax</h4></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Tag_(programming)" title="Tag (programming)">Tag (programming)</a></div>

</cfloop>

<cfoutput>#factorial#</cfoutput>

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="Fortran">Fortran</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Fortran" title="Fortran">Fortran</a></div>

<div class="mw-highlight mw-highlight-lang-fortran mw-content-ltr" dir="ltr"><pre>program FactorialProg

integer :: counter = 5

integer :: factorial = 1

do while (counter > 0)

end do

print *, factorial

end program FactorialProg

</pre></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Go_(programming_language)" title="Go (programming language)">Go (programming language)</a></div>

Go has no while statement, but it has the function of a for statement when omitting some elements of the for statement.

<div class="mw-highlight mw-highlight-lang-go mw-content-ltr" dir="ltr"><pre>counter, factorial := 5, 1

for counter > 1 {

counter, factorial = counter-1, factorial*counter

}

</pre></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Java_(programming_language)" title="Java (programming language)">Java (programming language)</a>, <a href="C_Sharp_(programming_language)" title="C Sharp (programming language)">C Sharp (programming language)</a>, and <a href="D_(programming_language)" title="D (programming language)">D (programming language)</a></div>

The code for the loop is the same for Java, C# and D:

<div class="mw-highlight mw-highlight-lang-csharp mw-content-ltr" dir="ltr"><pre>int counter = 5;

int factorial = 1;

while (counter > 1)

factorial *= counter--;

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="JavaScript">JavaScript</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="JavaScript" title="JavaScript">JavaScript</a></div>

<div class="mw-highlight mw-highlight-lang-javascript mw-content-ltr" dir="ltr"><pre>let counter = 5;

let factorial = 1;

factorial *= counter--;

console.log(factorial);

</pre></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Lua_(programming_language)" class="mw-redirect" title="Lua (programming language)">Lua (programming language)</a></div>

<div class="mw-highlight mw-highlight-lang-lua mw-content-ltr" dir="ltr"><pre>counter = 5

factorial = 1

while counter > 0 do

factorial = factorial * counter

counter = counter - 1

end

print(factorial)

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="MATLAB,_Octave">MATLAB, Octave</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="MATLAB" title="MATLAB">MATLAB</a> and <a href="GNU_Octave" title="GNU Octave">GNU Octave</a></div>

<div class="mw-highlight mw-highlight-lang-matlab mw-content-ltr" dir="ltr"><pre>counter = 5;

factorial = 1;

factorial = factorial * counter; %Multiply

counter = counter - 1; %Decrement

end

factorial

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="Mathematica">Mathematica</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Wolfram_Mathematica" class="mw-redirect" title="Wolfram Mathematica">Wolfram Mathematica</a> and <a href="Wolfram_Language" title="Wolfram Language">Wolfram Language</a></div>

<div class="mw-highlight mw-highlight-lang-mathematica mw-content-ltr" dir="ltr"><pre>Block[{counter=5,factorial=1}, (*localize counter and factorial*)

While[counter>0, (*While loop*)

factorial*=counter; (*Multiply*)

counter--; (*Decrement*)

];

factorial

]

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="Oberon,_Oberon-2,_Oberon-07,_Component_Pascal">Oberon, Oberon-2, Oberon-07, Component Pascal</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Oberon_(programming_language)" title="Oberon (programming language)">Oberon (programming language)</a>, <a href="Oberon-2" title="Oberon-2">Oberon-2</a>, <a href="Oberon-07" class="mw-redirect" title="Oberon-07">Oberon-07</a>, and <a href="Component_Pascal" title="Component Pascal">Component Pascal</a></div>

<div class="mw-highlight mw-highlight-lang-pascal mw-content-ltr" dir="ltr"><pre>MODULE Factorial;

IMPORT Out;

VAR

Counter, Factorial: INTEGER;

BEGIN

Counter := 5;

Factorial := 1;

WHILE Counter > 0 DO

Factorial := Factorial * Counter;

DEC(Counter)

END;

Out.Int(Factorial,0)

END Factorial.

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="Maya_Embedded_Language">Maya Embedded Language</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Maya_Embedded_Language" title="Maya Embedded Language">Maya Embedded Language</a></div>

<div class="mw-highlight mw-highlight-lang-perl mw-content-ltr" dir="ltr"><pre>int $counter = 5;

int $factorial = 1;

int $multiplication;

while ($counter > 0) {

$multiplication = $factorial * $counter;

$counter -= 1;

print("Counter is: " + $counter + ", multiplication is: " + $multiplication + "\n");

}

</pre></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Nim_(programming_language)" title="Nim (programming language)">Nim (programming language)</a></div>

<div class="mw-highlight mw-highlight-lang-nim mw-content-ltr" dir="ltr"><pre>var

counter = 5 # Set counter value to 5

factorial = 1 # Set factorial value to 1

while counter > 0: # While counter is greater than 0

dec counter # Set the counter to counter - 1.

echo factorial

</pre></div>

Non-terminating while loop:

<div class="mw-highlight mw-highlight-lang-nim mw-content-ltr" dir="ltr"><pre>while true:

echo "Help! I'm stuck in a loop!"

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="Pascal">Pascal</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Pascal_(programming_language)" title="Pascal (programming language)">Pascal (programming language)</a></div>

Pascal has two forms of the while loop, while and repeat. While repeats one statement (unless enclosed in a begin-end block) as long as the condition is true. The repeat statement repetitively executes a block of one or more statements through an until statement and continues repeating unless the condition is false. The main difference between the two is the while loop may execute zero times if the condition is initially false, the repeat-until loop always executes at least once.

<div class="mw-highlight mw-highlight-lang-pascal mw-content-ltr" dir="ltr"><pre>program Factorial1;

var

Fv: integer;

procedure fact(counter:integer);

var

Factorial: integer;

begin

Factorial := 1;

while Counter > 0 do

begin

Counter := Counter - 1

end;

WriteLn(Factorial)

end;

begin

Write('Enter a number to return its factorial: ');

readln(fv);

repeat

fact(fv);

Write('Enter another number to return its factorial (or 0 to quit): ');

until fv=0;

end.

</pre></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Perl" title="Perl">Perl</a></div>

<div class="mw-highlight mw-highlight-lang-perl mw-content-ltr" dir="ltr"><pre>my $counter = 5;

my $factorial = 1;

$factorial *= $counter--; # Multiply, then decrement

}

print $factorial;

</pre></div>

While loops are frequently used for reading data line by line (as defined by the <code>$/</code> line separator) from open filehandles:

<div class="mw-highlight mw-highlight-lang-perl mw-content-ltr" dir="ltr"><pre>open IN, "<test.txt";

while (<IN>) {

print;

}

close IN;

</pre></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="PHP" title="PHP">PHP</a></div>

<div class="mw-highlight mw-highlight-lang-php mw-content-ltr" dir="ltr"><pre>$counter = 5;

$factorial = 1;

while ($counter > 0) {

$factorial *= $counter--; // Multiply, then decrement.

}

echo $factorial;

</pre></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="PL/I" title="PL/I">PL/I</a></div>

<div class="mw-highlight mw-highlight-lang-rexx mw-content-ltr" dir="ltr"><pre>declare counter fixed initial(5);

declare factorial fixed initial(1);

do while(counter > 0)

factorial = factorial * counter;

counter = counter - 1;

end;

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="Python">Python</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Python_(programming_language)" title="Python (programming language)">Python (programming language)</a></div>

<div class="mw-highlight mw-highlight-lang-python mw-content-ltr" dir="ltr"><pre>counter = 5 # Set the value to 5

factorial = 1 # Set the value to 1

while counter > 0: # While counter(5) is greater than 0

factorial *= counter # Set new value of factorial to counter.

counter -= 1 # Set the counter to counter - 1.

print(factorial) # Print the value of factorial.

</pre></div>

Non-terminating while loop:

<div class="mw-highlight mw-highlight-lang-python mw-content-ltr" dir="ltr"><pre>while True:

print("Help! I'm stuck in a loop!")

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="Racket">Racket</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Racket_(programming_language)" title="Racket (programming language)">Racket (programming language)</a> and <a href="Scheme_(programming_language)" title="Scheme (programming language)">Scheme (programming language)</a></div>

In Racket, as in other <a href="Scheme_(programming_language)" title="Scheme (programming language)">Scheme</a> implementations, a named-let is a popular way to implement loops:

<div class="mw-highlight mw-highlight-lang-racket mw-content-ltr" dir="ltr"><pre>#lang racket

(define counter 5)

(define factorial 1)

(let loop ()

(when (> counter 0)

(set! factorial (* factorial counter))

(set! counter (sub1 counter))

(loop)))

(displayln factorial)

</pre></div>

Using a macro system, implementing a while loop is a trivial exercise (commonly used to introduce macros):

<div class="mw-highlight mw-highlight-lang-racket mw-content-ltr" dir="ltr"><pre>#lang racket

(define-syntax-rule (while test body ...) ; implements a while loop

(let loop () (when test body ... (loop))))

(define counter 5)

(define factorial 1)

(while (> counter 0)

(displayln factorial)

</pre></div>

However, an imperative programming style is often discouraged in Scheme and Racket.

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Ruby_(programming_language)" title="Ruby (programming language)">Ruby (programming language)</a></div>

<div class="mw-highlight mw-highlight-lang-ruby mw-content-ltr" dir="ltr"><pre># Calculate the factorial of 5

i = 1

factorial = 1

while i <= 5

factorial *= i

i += 1

end

puts factorial

</pre></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Rust_(programming_language)" title="Rust (programming language)">Rust (programming language)</a></div>

<div class="mw-highlight mw-highlight-lang-rust mw-content-ltr" dir="ltr"><pre>fn main() {

let mut counter = 5;

let mut factorial = 1;

while counter > 1 {

factorial *= counter;

counter -= 1;

}

println!("{}", factorial);

}

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="Smalltalk">Smalltalk</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Smalltalk" title="Smalltalk">Smalltalk</a></div>

Contrary to other languages, in Smalltalk a while loop is not a <a href="Language_construct" title="Language construct">language construct</a> but defined in the class <code>BlockClosure</code> as a method with one parameter, the body as a <a href="Closure_(computer_programming)" title="Closure (computer programming)">closure</a>, using self as the condition.

Smalltalk also has a corresponding whileFalse: method.

<div class="mw-highlight mw-highlight-lang-smalltalk mw-content-ltr" dir="ltr"><pre>| count factorial |

count := 5.

factorial := 1.

[count > 0] whileTrue:

[factorial := factorial * count.

count := count - 1].

Transcript show: factorial

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="Swift">Swift</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Swift_(programming_language)" title="Swift (programming language)">Swift (programming language)</a></div>

<div class="mw-highlight mw-highlight-lang-swift mw-content-ltr" dir="ltr"><pre>var counter = 5 // Set the initial counter value to 5

var factorial = 1 // Set the initial factorial value to 1

while counter > 0 { // While counter(5) is greater than 0

factorial *= counter // Set new value of factorial to factorial x counter.

counter -= 1 // Set the new value of counter to counter - 1.

}

print(factorial) // Print the value of factorial.

</pre></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="Tcl" title="Tcl">Tcl</a></div>

<div class="mw-highlight mw-highlight-lang-tcl mw-content-ltr" dir="ltr"><pre>set counter 5

set factorial 1

while {$counter > 0} {

set factorial [expr $factorial * $counter]

incr counter -1

}

puts $factorial

</pre></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="VEX_prefix" title="VEX prefix">VEX prefix</a></div>

printf("%d", factorial);

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="PowerShell">PowerShell</h3></div>

<div role="note" class="hatnote navigation-not-searchable">Further information: <a href="PowerShell" title="PowerShell">PowerShell</a></div>

<div class="mw-highlight mw-highlight-lang-powershell mw-content-ltr" dir="ltr"><pre>$counter = 5

$factorial = 1

while ($counter) {

$factorial *= $counter--

}

$factorial

</pre></div>

<div class="mw-heading mw-heading3"><h3 id="While_(language)">While (language)</h3></div>

While<a href="#cite_note-3">[3]</a> is a simple programming language constructed from assignments, sequential composition, conditionals, and while statements, used in the theoretical analysis of imperative programming language <a href="Semantics_(computer_science)" title="Semantics (computer science)">semantics</a>.<a href="#cite_note-NielsonNielson1999-4">[4]</a><a href="#cite_note-5">[5]</a>

<div class="mw-highlight mw-highlight-lang-whiley mw-content-ltr" dir="ltr"><pre>C := 5;

F := 1;

while (C > 1) do

F := F * C;

C := C - 1;

</pre></div>

<ul><li><a href="Do_while_loop" title="Do while loop">Do while loop</a></li>

<li><a href="Foreach" class="mw-redirect" title="Foreach">Foreach</a></li>

<li><a href="Primitive_recursive_function" title="Primitive recursive function">Primitive recursive function</a></li>

<li><a href="General_recursive_function" title="General recursive function">General recursive function</a></li>

<li><a href="LOOP_(programming_language)" title="LOOP (programming language)">LOOP (programming language)</a> – a programming language with the property that the functions it can compute are exactly the primitive recursive functions</li></ul>

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

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/* end https://en.wikipedia.org/ */

</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://docs.oracle.com/javase/tutorial/java/nutsandbolts/while.html">"The while and do-while Statements (The Java Tutorials > Learning the Java Language > Language Basics)"</a>. Dosc.oracle.com. Retrieved 2016-10-21.</cite>

</li>

<li id="cite_note-2"><a href="#cite_ref-2">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://msdn.microsoft.com/en-us/library/2aeyhxcd.aspx">"while (C# reference)"</a>. Msdn.microsoft.com. Retrieved 2016-10-21.</cite>

</li>

<li id="cite_note-3"><a href="#cite_ref-3">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://profs.sci.univr.it/~merro/files/WhileExtra_l.pdf">"Chapter 3: The While programming language"</a> (PDF). Profs.sci.univr.it. Retrieved 2016-10-21.</cite>

</li>

<li id="cite_note-NielsonNielson1999-4"><a href="#cite_ref-NielsonNielson1999_4-0">^</a> <cite id="CITEREFFlemming_NielsonHanne_R._NielsonChris_Hankin1999" class="citation book cs1">Flemming Nielson; Hanne R. Nielson; Chris Hankin (1999). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=RLjt0xSj8DcC">Principles of Program Analysis</a>. Springer. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-3-540-65410-0</bdi>. Retrieved 29 May 2013.</cite>

</li>

<li id="cite_note-5"><a href="#cite_ref-5">^</a> <cite id="CITEREFIllingworth1997" class="citation book cs1">Illingworth, Valerie (11 December 1997). <a rel="nofollow" class="external text" href="https://archive.org/details/dictionaryofcomp00illi">Dictionary of Computing</a>. Oxford Paperback Reference (4th ed.). Oxford University Press. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>9780192800466</bdi>.</cite>

</li>

</ol></div></div></div><div><div class="zim-footer">

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