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    <p>There are <em>several</em> ways to convert the code in the question to Scheme. The first one I can think of:</p> <pre><code>(define (print-even n) (let loop ((i 0)) (if (&lt;= i n) (begin (print i) (newline) (loop (+ i 2)))))) </code></pre> <p>Notice this:</p> <ul> <li>The solution is written as a recursive procedure</li> <li>Instead of a <code>for</code> loop, I'm using a construct called a <em>named let</em>, which permits the initialization of some iteration variables (<code>i</code> in this case, initialized to <code>0</code>) and the repeated execution of a recursive procedure (<code>loop</code> in this case), producing an effect similar to a <code>for</code>, even in performance</li> <li>The stop condition in the "loop" is handled with essentially the same expression: repeat the body of the iteration as long as <code>(&lt;= i n)</code>, when that condition becomes false, the iteration ends</li> <li>The <code>begin</code> surrounds the body of the "loop", just as the curly braces <code>{}</code> do in the original code</li> <li>The <code>print</code> procedure performs the expected operation; for readability I added a new line after printing each number</li> <li>The increment part of the original loop <code>i += 2</code> is handled by the expression <code>(+ i 2)</code>, inside the recursive call</li> </ul> <p>So you see, the process being executed is essentially the same, only the way to <em>write</em> it (the syntax!) is different. Give it a try, type this:</p> <pre><code>(print-even 6) </code></pre> <p>... And the following will get printed on the screen:</p> <pre><code>0 2 4 6 </code></pre> <p>Another possible way to implement the procedure, more similar to the original code, although (this is completely subjective) less idiomatic than the previous one:</p> <pre><code>(define (print-even n) (do ((i 0 (+ i 2))) ((&gt; i n)) (print i) (newline))) </code></pre> <p>Finally, if you're using <a href="http://racket-lang.org/" rel="nofollow">Racket</a> this will seem even more familiar to you:</p> <pre><code>#lang racket (define (print-even n) (for ((i (in-range 0 (+ n 1) 2))) (print i) (newline))) </code></pre>
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    1. POHow to convert this code to Scheme
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    1. POHow to convert this code to Scheme
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    1. COThis works. Thanks very much
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