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    <p>Yes, Haskell has variables. Consider the (essentially equivalent) definitions </p> <pre><code>inc n = n + 1 inc = \n -&gt; n + 1 </code></pre> <p>In both these cases, <code>n</code> is a variable; it will take on different values at different times. The <a href="http://www.haskell.org/onlinereport/" rel="noreferrer">Haskell Report</a>, in <a href="http://www.haskell.org/onlinereport/exps.html" rel="noreferrer">Section 3</a> refers to these explicitly as variables.</p> <p>That <code>n</code> here is a variable may be easier to see if we consider the following complete program:</p> <pre><code>inc n = n + 1 f = inc 0 g = inc 1 main = print (f+g) </code></pre> <p>The answer printed will be "3", of course. When evaluating <code>f</code>, as we expand <code>inc</code> <code>x</code> will take on the value <code>0</code>, and when later (or earlier!) evaluating <code>g</code>, as we expand <code>inc</code> <code>x</code> will take on the value <code>1</code>.</p> <p>Some confusion may have arisen because Haskell, as with the other languages listed in the question, is a single-assignment language: it does not allow the reassignment of variables within a scope. Once <code>n</code> has been assigned the value <code>42</code>, it cannot be anything but 42 without introducing a new scope with a new <code>n</code> (which is a different variable, shadowing the other <code>n</code>) bound to another value.</p> <p>This may not be entirely obvious in some contexts, such as expressions using <code>do</code>:</p> <pre><code> do let n = 1 print n let n = 2 print n </code></pre> <p>but if you remove the syntactic sugar, translating it into Haskell without the <code>do</code>, it becomes clear that there was a new, nested scope created where the <code>n</code> in that inner scope is a different variable that is shadowing the <code>n</code> in the outer scope:</p> <pre><code>(let n = 1 in (print n &gt;&gt; (let n = 2 in print n))) </code></pre>
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    1. PODoes Haskell have variables?
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    1. COThere are no variables in Haskell! Variables may be reassigned. What you have in functions or let-bindings is nothing but an immutable function argument, a value that is bound to a name!
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    2. CODario, wikipedia disagrees, listing nine languages where all variables are single-assignment and another five where single-assignment is an option: http://en.wikipedia.org/wiki/Single_assignment . Additionally, mathematicians, who came up with the term, also use variables in the single-assignment sense. If you're going to argue against this, how about posting a detailed answer showing why this is an incorrect view?
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