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<p class="MsoNormal">“CE” was just an example of a less common acronym. I think such an acronym<o:p></o:p></p>
<p class="MsoNormal">can be used for various purposes, so it is probably quite local in the code what it<o:p></o:p></p>
<p class="MsoNormal">stands for.<o:p></o:p></p>
<p class="MsoNormal">We also have other (I think more common) acronyms like TLI for<o:p></o:p></p>
<p class="MsoNormal">TargetLoweringInfo, or MF for MachineFunction.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">As Krzystzof were saying “Long names should be used where <o:p>
</o:p></p>
<p class="MsoNormal">meaning needs to be conveyed, otherwise they just obfuscate the code
<o:p></o:p></p>
<p class="MsoNormal">needlessly.”<o:p></o:p></p>
<p class="MsoNormal">Having to write out targetLoweringInfo instead of the short form TLI<o:p></o:p></p>
<p class="MsoNormal">everywhere would probably obfuscate things (lots of long lines, line splits)<o:p></o:p></p>
<p class="MsoNormal">rather than making things easier to read/understand.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">FWIW, there is a proposal in the RFC, and the coding standard still say that<o:p></o:p></p>
<p class="MsoNormal">acronyms may be used. I still haven’t seen any answers about what the<o:p></o:p></p>
<p class="MsoNormal">“correct way” would be when using an acronym if the RFC is accepted.<o:p></o:p></p>
<p class="MsoNormal">I’ve only seen answers about _<i>not</i>_ using acronyms, but that has not part<o:p></o:p></p>
<p class="MsoNormal">of the RFC afaict.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">My point was that the RFC need to be clear about what to do with the<o:p></o:p></p>
<p class="MsoNormal">acronyms if we go down that path.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">/Björn<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b>From:</b> Chris Lattner <clattner@nondot.org> <br>
<b>Sent:</b> den 13 februari 2019 10:00<br>
<b>To:</b> Björn Pettersson A <bjorn.a.pettersson@ericsson.com><br>
<b>Cc:</b> Michael Platings <Michael.Platings@arm.com>; llvm-dev@lists.llvm.org<br>
<b>Subject:</b> Re: [llvm-dev] changing variable naming rules in LLVM codebase<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Feb 12, 2019, at 4:02 AM, Björn Pettersson A via llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">(Sorry if this subject already has been discussed, but I could not find any clear rules/recommendations.)<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">What would the recommendation be for acronyms (I’ve seen the rule about avoiding them unless they are “well known”,<o:p></o:p></p>
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<p class="MsoNormal">but sometimes an acronym is useful, and we at least need to have some recommendation for the “well known” ones).<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">Example:<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal"> if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V))<o:p></o:p></p>
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<p class="MsoNormal"> if (CE->getOpcode() == Instruction::GetElementPtr &&<o:p></o:p></p>
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<p class="MsoNormal"> CE->getOperand(0)->isNullValue()) {<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">In the above example, is the recommendation to use “ce” instead of “CE” now? Or should it be “cE”?<o:p></o:p></p>
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<p class="MsoNormal">With lowerCamelCase one might think that “cE” is the correct one (although I personally think that one looks quite ugly).<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">In most examples, you’d use something other than an initialism. I was the one who started the whole CE thing as a contraction of the type into something short, but there are almost always things that work otherwise. For example, I’d now
write that example as:<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"> if (ConstantExpr *expr = dyn_cast<ConstantExpr>(value))<br>
if (expr->getOpcode() == Instruction::GetElementPtr &&<br>
expr->getOperand(0)->isNullValue()) {<o:p></o:p></p>
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<p class="MsoNormal">or perhaps ‘constant' instead of ‘expr’.<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">Maybe there should be an exception that variable names that start with an acronym still should start with an upper case letter?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">That would also be fine with me - it could push such a debate down the road, and is definitely important for a transition period anyway.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-Chris<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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