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<br><div><div>On Feb 17, 2009, at 6:20 AM, James Coglan wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: 'Lucida Grande'; font-size: 12px; 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: 0; ">... in the Scheme spec it says that operands are to be evaluated in an unspecified order.<span class="Apple-converted-space">�...</span></span></blockquote><br></div><div>Here is the meaning of this statement. Say you have an application with several subexpressions�</div><div><br></div><div>�(M n K)</div><div><br></div><div>and at least two of them are NOT values yet, say, M and K. Then the compiler can arrange two different sequences�</div><div><br></div><div>�evaluate�M,�store�away�value�m</div><div>�evaluate�K,�store�away�value�k</div><div>�test�that�m�is�a�function�and�then�call�m{n,k}</div><div><br></div><div>OR�</div><div><br></div><div>�evaluate�K,�store�away�value�k</div><div>�evaluate�M,�store�away�value�m</div><div>�test�that�m�is�a�function�and�then�call�m{n,k}</div><div><br></div><div>Now take a look at your program and check whether it contains such an application. NB, application includes such things as (+ 1 2).�</div><div><br></div><div><br></div><div>-- Matthias</div><div><br></div><div><br></div><br></body></html>