<table><tr><td style="">markg requested changes to this revision.<br />markg added a reviewer: markg.<br />markg added inline comments.<br />This revision now requires changes to proceed.
</td><a style="text-decoration: none; padding: 4px 8px; margin: 0 8px 8px; float: right; color: #464C5C; font-weight: bold; border-radius: 3px; background-color: #F7F7F9; background-image: linear-gradient(to bottom,#fff,#f1f0f1); display: inline-block; border: 1px solid rgba(71,87,120,.2);" href="https://phabricator.kde.org/D4012" rel="noreferrer">View Revision</a></tr></table><br /><div><strong>INLINE COMMENTS</strong><div><div style="margin: 6px 0 12px 0;"><div style="border: 1px solid #C7CCD9; border-radius: 3px;"><div style="padding: 0; background: #F7F7F7; border-color: #e3e4e8; border-style: solid; border-width: 0 0 1px 0; margin: 0;"><div style="color: #74777d; background: #eff2f4; padding: 6px 8px; overflow: hidden;"><a style="float: right; text-decoration: none;" href="https://phabricator.kde.org/D4012#inline-15860" rel="noreferrer">View Inline</a><span style="color: #4b4d51; font-weight: bold;">units.cpp:61</span></div>
<div style="font: 11px/15px "Menlo", "Consolas", "Monaco", monospace; white-space: pre-wrap; clear: both; padding: 4px 0; margin: 0;"><div style="padding: 0 8px; margin: 0 4px; "><span class="n">SharedAppFilter</span> <span style="color: #aa2211">*</span><span class="n">Units</span><span style="color: #aa2211">::</span><span class="n">s_sharedAppFilter</span> <span style="color: #aa2211">=</span> <span style="color: #aa4000">nullptr</span><span class="p">;</span>
</div><div style="padding: 0 8px; margin: 0 4px; background: #d0ffd0;"><span class="n">Units</span> <span style="color: #aa2211">*</span><span class="n">Units</span><span style="color: #aa2211">::</span><span class="n">s_self</span> <span style="color: #aa2211">=</span> <span style="color: #aa4000">nullptr</span><span class="p">;</span>
</div></div></div>
<div style="margin: 8px 0; padding: 0 12px;"><p style="padding: 0; margin: 8px;">Remove this line if you go for the comment i made below.</p></div></div><br /><div style="border: 1px solid #C7CCD9; border-radius: 3px;"><div style="padding: 0; background: #F7F7F7; border-color: #e3e4e8; border-style: solid; border-width: 0 0 1px 0; margin: 0;"><div style="color: #74777d; background: #eff2f4; padding: 6px 8px; overflow: hidden;"><a style="float: right; text-decoration: none;" href="https://phabricator.kde.org/D4012#inline-15859" rel="noreferrer">View Inline</a><span style="color: #4b4d51; font-weight: bold;">units.cpp:98-104</span></div>
<div style="font: 11px/15px "Menlo", "Consolas", "Monaco", monospace; white-space: pre-wrap; clear: both; padding: 4px 0; margin: 0;"><div style="padding: 0 8px; margin: 0 4px; background: #d0ffd0;"><span class="n">Units</span> <span style="color: #aa2211">*</span><span class="n">Units</span><span style="color: #aa2211">::</span><span class="n">self</span><span class="p">()</span>
</div><div style="padding: 0 8px; margin: 0 4px; background: #d0ffd0;"><span class="p">{</span>
</div><div style="padding: 0 8px; margin: 0 4px; background: #d0ffd0;"> <span style="color: #aa4000">if</span> <span class="p">(</span><span style="color: #aa2211">!</span><span class="n">s_self</span><span class="p">)</span> <span class="p">{</span>
</div><div style="padding: 0 8px; margin: 0 4px; background: #d0ffd0;"> <span class="n">s_self</span> <span style="color: #aa2211">=</span> <span style="color: #aa4000">new</span> <span class="n">Units</span><span class="p">();</span>
</div><div style="padding: 0 8px; margin: 0 4px; background: #d0ffd0;"> <span class="p">}</span>
</div><div style="padding: 0 8px; margin: 0 4px; background: #d0ffd0;"> <span style="color: #aa4000">return</span> <span class="n">s_self</span><span class="p">;</span>
</div><div style="padding: 0 8px; margin: 0 4px; "><span class="p">}</span>
</div></div></div>
<div style="margin: 8px 0; padding: 0 12px;"><p style="padding: 0; margin: 8px;">I think you need to do more, or rather less.<br />
In C++11 making a singleton is really easy! All you need is:</p>
<div class="remarkup-code-block" style="margin: 12px 0;" data-code-lang="text" data-sigil="remarkup-code-block"><pre class="remarkup-code" style="font: 11px/15px "Menlo", "Consolas", "Monaco", monospace; padding: 12px; margin: 0; background: rgba(71, 87, 120, 0.08);">Units &Units::self()
{
static Units units;
return units;
}</pre></div>
<p style="padding: 0; margin: 8px;">And done. It gives you a thread safe singleton (which your current version isn't).<br />
I also think the current compiler requirements for plasma and frameworks allow you to use the code I've just given.. So.. Use it :)<br />
Note: i changed the return value to a reference.</p>
<p style="padding: 0; margin: 8px;">Also, why use "self" as getter for a singleton? I think "instance" or "getInstance" is the most used name for this, but i might be wrong here.</p></div></div><br /><div style="border: 1px solid #C7CCD9; border-radius: 3px;"><div style="padding: 0; background: #F7F7F7; border-color: #e3e4e8; border-style: solid; border-width: 0 0 1px 0; margin: 0;"><div style="color: #74777d; background: #eff2f4; padding: 6px 8px; overflow: hidden;"><a style="float: right; text-decoration: none;" href="https://phabricator.kde.org/D4012#inline-15864" rel="noreferrer">View Inline</a><span style="color: #4b4d51; font-weight: bold;">units.h:122</span></div>
<div style="font: 11px/15px "Menlo", "Consolas", "Monaco", monospace; white-space: pre-wrap; clear: both; padding: 4px 0; margin: 0;"><div style="padding: 0 8px; margin: 0 4px; background: #d0ffd0;"> <span style="color: #aa4000">static</span> <span class="n">Units</span> <span style="color: #aa2211">*</span><span style="color: #004012">self</span><span class="p">();</span>
</div></div></div>
<div style="margin: 8px 0; padding: 0 12px;"><p style="padding: 0; margin: 8px;">Add documentation please.</p></div></div><br /><div style="border: 1px solid #C7CCD9; border-radius: 3px;"><div style="padding: 0; background: #F7F7F7; border-color: #e3e4e8; border-style: solid; border-width: 0 0 1px 0; margin: 0;"><div style="color: #74777d; background: #eff2f4; padding: 6px 8px; overflow: hidden;"><a style="float: right; text-decoration: none;" href="https://phabricator.kde.org/D4012#inline-15863" rel="noreferrer">View Inline</a><span style="color: #4b4d51; font-weight: bold;">units.h:185-186</span></div>
<div style="font: 11px/15px "Menlo", "Consolas", "Monaco", monospace; white-space: pre-wrap; clear: both; padding: 4px 0; margin: 0;"><div style="padding: 0 8px; margin: 0 4px; "><span style="color: #a0a000">private</span><span class="p">:</span>
</div><div style="padding: 0 8px; margin: 0 4px; background: #d0ffd0;"> <span class="n">Units</span><span class="p">(</span><span class="n">QObject</span> <span style="color: #aa2211">*</span><span class="n">parent</span> <span style="color: #aa2211">=</span> <span style="color: #601200">0</span><span class="p">);</span>
</div><div style="padding: 0 8px; margin: 0 4px; background: #d0ffd0;"> <span class="n">Q_DISABLE_COPY</span><span class="p">(</span><span class="n">Units</span><span class="p">)</span>
</div></div></div>
<div style="margin: 8px 0; padding: 0 12px;"><p style="padding: 0; margin: 8px;">If this were pre C++11, you'd be done :)<br />
But we have move semantics now. You need to disable moving as well!</p>
<div class="remarkup-code-block" style="margin: 12px 0;" data-code-lang="text" data-sigil="remarkup-code-block"><pre class="remarkup-code" style="font: 11px/15px "Menlo", "Consolas", "Monaco", monospace; padding: 12px; margin: 0; background: rgba(71, 87, 120, 0.08);">Units(Units const&) = delete; // Copy construct
Units(Units&&) = delete; // Move construct
Units& operator=(Units const&) = delete; // Copy assign
Units& operator=(Units &&) = delete; // Move assign</pre></div>
<p style="padding: 0; margin: 8px;">I'd drop the Q_DISABLE_COPY and go for the above "= delete" lines, but that's up for you to decide. You have to add them for move semantics anyway (Q_DISABLE_COPY does not do that for you).</p></div></div><br /><div style="border: 1px solid #C7CCD9; border-radius: 3px;"><div style="padding: 0; background: #F7F7F7; border-color: #e3e4e8; border-style: solid; border-width: 0 0 1px 0; margin: 0;"><div style="color: #74777d; background: #eff2f4; padding: 6px 8px; overflow: hidden;"><a style="float: right; text-decoration: none;" href="https://phabricator.kde.org/D4012#inline-15861" rel="noreferrer">View Inline</a><span style="color: #4b4d51; font-weight: bold;">units.h:200</span></div>
<div style="font: 11px/15px "Menlo", "Consolas", "Monaco", monospace; white-space: pre-wrap; clear: both; padding: 4px 0; margin: 0;"><div style="padding: 0 8px; margin: 0 4px; "> <span style="color: #aa4000">static</span> <span class="n">SharedAppFilter</span> <span style="color: #aa2211">*</span><span class="n">s_sharedAppFilter</span><span class="p">;</span>
</div><div style="padding: 0 8px; margin: 0 4px; background: #d0ffd0;"> <span style="color: #aa4000">static</span> <span class="n">Units</span> <span style="color: #aa2211">*</span><span class="n">s_self</span><span class="p">;</span>
</div></div></div>
<div style="margin: 8px 0; padding: 0 12px;"><p style="padding: 0; margin: 8px;">Remove this line if you go for the comment i made below.</p></div></div></div></div></div><br /><div><strong>REPOSITORY</strong><div><div>R242 Plasma Frameworks</div></div></div><br /><div><strong>REVISION DETAIL</strong><div><a href="https://phabricator.kde.org/D4012" rel="noreferrer">https://phabricator.kde.org/D4012</a></div></div><br /><div><strong>EMAIL PREFERENCES</strong><div><a href="https://phabricator.kde.org/settings/panel/emailpreferences/" rel="noreferrer">https://phabricator.kde.org/settings/panel/emailpreferences/</a></div></div><br /><div><strong>To: </strong>broulik, Plasma, davidedmundson, markg<br /><strong>Cc: </strong>markg, plasma-devel, Frameworks, lesliezhai, ali-mohamed, jensreuterberg, abetts, andreaska, sebas<br /></div>