<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Apr 3, 2012, at 9:34 AM, Roelof Wobben wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">
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I have to make this exercise : <br>
<br>
Design the function <span class="RktSym">different</span>. It
consumes
two (<a href="http://www.ccs.neu.edu/home/matthias/HtDP2e/htdp2e-part1.html#%28counter._data-uni._%28exercise._struct9%29%29" pltdoc="x">representations of</a>) three-letter words and creates
a word from the
differences. For each position in the words, it uses the letter from
the
second word, if the two are the same; otherwise it uses the marker
<span class="RktVal">"*"</span>. Note: The problem statement
mentions two different
tasks: one concerning words and one concerning letters. This
suggests that
you design two functions.<br>
<br>
Im my opion I only need 1 function.<br>
<br>
I use a cond to check if the letters are the same and if print the
letter otherwise print x .<br></div></blockquote><div><br></div></div><div>I can imagine doing this as a single function, but I agree that it would be cleaner and more modifiable if it were done as two functions, "one concerning words and one concerning letters."</div><div><br></div><div><div>What is the contract of your 1 function?</div><div><br></div></div><br><br><div>
<span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>Stephen Bloch</div><div><a href="mailto:sbloch@adelphi.edu">sbloch@adelphi.edu</a></div></div></span></span>
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