<div class="gmail_quote">2009/1/23 Olex P <span dir="ltr"><<a href="mailto:hoknamahn@gmail.com">hoknamahn@gmail.com</a>></span><br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
Hello Haskellers!<br>It's probably a simple question but I can't find a proper solution...<br>Suppose we have a class Vector which overloads (+) operation. I'd like to represent a Matrix data type as a set of vectors:<br>
<br>data Matrix3 = M3 !Vector3 !Vector3 !Vector3<br><br>In this case (+) for matrices could be implemented as:<br><br> (M3 r11 r12 r13) + (M3 r21 r22 r23) = M3 (r11 + r21) (r12 + r22) (r13 + r23)<br><br>But GHC says about ambiguous occurrence. I don't understand why because it's should be pretty clear that rows are vectors and (+) has to be vector type as well. I could use Vector.+ instead but it doesn't look good.<br>
Probably I'm missing something. Any ideas?</blockquote><div><br></div><div>I'm am seeing an image. It's a... a Vector class, with an operation (+). Oh, he's with another one though. It's the Num class. Oh they're fighting over the (+). Vector is trying to take it from Num, but Num isn't letting go.</div>
<div><br></div><div>Why doesn't Vector see that there is a whole pile of operations neglected in the corner, like (^+^), (.+.). He just really wants that (+), huh...</div><div><br></div><div>Luke</div></div>