Hello everyone,<div><br></div><div>I have the simple applicative parser combinator:</div><div><br></div><div>parseLabel = Label &lt;$&gt; (between spaces (char &#39;:&#39;) (many1 alphaNum))<br></div><div><br></div><div>This gives me the error:</div>
<div><div><br></div><div>No instance for (Stream s m Char)</div><div>      arising from a use of `spaces&#39; at tree.hs:18:32-37</div><div>    Possible fix: add an instance declaration for (Stream s m Char)</div><div>    In the first argument of `between&#39;, namely `spaces&#39;</div>
<div>    In the second argument of `(&lt;$&gt;)&#39;, namely</div><div>        `(between spaces (char &#39;:&#39;) (many1 alphaNum))&#39;</div><div>    In the expression:</div><div>          Label &lt;$&gt; (between spaces (char &#39;:&#39;) (many1 alphaNum))</div>
<div><br></div><div>When I test this function in ghci, I have no problems, yet whenever I try to open it in a file it fails. What am I doing wrong?</div><div>For those who are curious, Label is a data constructor in the following data type:</div>
<div><div><br></div><div>data Loc = Label String</div><div><span class="Apple-tab-span" style="white-space:pre">		</span> | Addr Int</div><div><span class="Apple-tab-span" style="white-space:pre">		</span>deriving Show</div>
<div><br></div><div>Thanks!</div><div>Ian Duncan</div></div></div>