<div dir="ltr">Hello,<br><br>&nbsp;&nbsp; I am reading some extant Haskell code that uses Posix signals.... I am confused by the motivation of the following ...<br><br><table class="vanilla" cellpadding="0" cellspacing="0"><tbody><tr>
<td class="decl"><span class="keyword">type</span> <a href="http://hackage.haskell.org/packages/archive/unix/2.3.0.0/doc/html/System-Posix-Signals.html#t%3ASignal">Signal</a> = <a href="http://hackage.haskell.org/packages/archive/base/3.0.1.0/doc/html/Foreign-C-Types.html#t%3ACInt">CInt</a></td>
</tr><tr><td class="s8"><br></td></tr><tr><td class="decl"><a href="http://hackage.haskell.org/packages/archive/unix/2.3.0.0/doc/html/System-Posix-Signals.html#v%3AnullSignal">nullSignal</a> :: <a href="http://hackage.haskell.org/packages/archive/unix/2.3.0.0/doc/html/System-Posix-Signals.html#t%3ASignal">Signal</a></td>
</tr><tr><td class="s8"><br></td></tr><tr><td class="decl"><a href="http://hackage.haskell.org/packages/archive/unix/2.3.0.0/doc/html/System-Posix-Signals.html#v%3AinternalAbort">internalAbort</a> :: <a href="http://hackage.haskell.org/packages/archive/unix/2.3.0.0/doc/html/System-Posix-Signals.html#t%3ASignal">Signal</a></td>
</tr><tr><td class="s8"><br></td></tr><tr><td class="decl"><a href="http://hackage.haskell.org/packages/archive/unix/2.3.0.0/doc/html/System-Posix-Signals.html#v%3AsigABRT">sigABRT</a> :: <a href="http://hackage.haskell.org/packages/archive/base/3.0.1.0/doc/html/Foreign-C-Types.html#t%3ACInt">CInt</a></td>
</tr><tr><td class="s8"><br></td></tr><tr><td class="decl"><a href="http://hackage.haskell.org/packages/archive/unix/2.3.0.0/doc/html/System-Posix-Signals.html#v%3ArealTimeAlarm">realTimeAlarm</a> :: <a href="http://hackage.haskell.org/packages/archive/unix/2.3.0.0/doc/html/System-Posix-Signals.html#t%3ASignal">Signal</a></td>
</tr><tr><td class="s8"><br></td></tr><tr><td class="decl"><a href="http://hackage.haskell.org/packages/archive/unix/2.3.0.0/doc/html/System-Posix-Signals.html#v%3AsigALRM">sigALRM</a> :: <a href="http://hackage.haskell.org/packages/archive/base/3.0.1.0/doc/html/Foreign-C-Types.html#t%3ACInt">CInt</a></td>
</tr><tr><td class="s8"><br></td></tr><tr><td class="decl"><a href="http://hackage.haskell.org/packages/archive/unix/2.3.0.0/doc/html/System-Posix-Signals.html#v%3AbusError">busError</a> :: <a href="http://hackage.haskell.org/packages/archive/unix/2.3.0.0/doc/html/System-Posix-Signals.html#t%3ASignal">Signal</a></td>
</tr><tr><td class="s8"><br></td></tr><tr><td class="decl"><a href="http://hackage.haskell.org/packages/archive/unix/2.3.0.0/doc/html/System-Posix-Signals.html#v%3AsigBUS">sigBUS</a> :: <a href="http://hackage.haskell.org/packages/archive/base/3.0.1.0/doc/html/Foreign-C-Types.html#t%3ACInt">CInt</a></td>
</tr></tbody></table><br><br>OK .. &quot;type&quot; is really just a synomym and doesn&#39;t invoke type checking like &quot;data&quot; type declarations do .. so why don&#39;t we have all the &quot;CInts&quot; substituted by &quot;Signal&quot;? I.e. what did I miss?<br>
<br>Thanks, Vasili<br></div>