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<p class="MsoNormal"><span lang="EN-US">Hi all<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I was wondering if named record patterns `o instanceof Pair(String left, String right) pair` are still on the table for the future or not. (Not sure if 'named' record pattern is the right name?)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">IIRC they were shelfed due to the ambiguity that they could cause in this case, if there also exists a function `when`:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">```<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">switch(o) {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> case Pair(String left, String right) when when (left == right) -> ...<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">}<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">```<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">It feels weird to me however that this feature was shelved just for this case, when a 'simple' rule could be introduced that a record pattern can't introduce a pattern variable with the name of a contextual keyword or
at least not `when`.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Are there other reasons that record patterns can't introduce a variable that matches the whole pair anymore? It feels like it could be useful, even more so with JEP 443: Unnamed Patterns and Variables (Preview)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">```<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">if (o instanceof ColoredPoint(Point(_, int y), _) cp && y > 0) {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> doAction(cp);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">}<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">```<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Instead of<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">```<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">if (o instanceof ColoredPoint(Point(int x, int y), Color c) && y > 0) {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> doAction(new ColoredPoint(new Point(x, y), c));<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">}<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">```<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">or this, if ColoredPoint can both hold `Point` and `Point3D`<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">```<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">if (o instanceof ColoredPoint cp && cp.point() instanceof Point(_, int y) && y > 0) {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> doAction(cp);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">}<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">```<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">or if it can only hold `Point`<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">```<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">if (o instanceof ColoredPoint cp && cp.point().y() > 0) {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> doAction(cp);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">}<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">```<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Greetings<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Robbe Pincket<o:p></o:p></span></p>
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