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<p class="MsoNormal"><span style="mso-fareast-language:EN-US">If we are always going to generate a parse tree with annotations from the parser, let’s not generate two!<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">I’m fine with always generating the annotations, but we just need to check that it doesn’t have insupportable costs.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Simon<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US">From:</span></b><span lang="EN-US"> Alan & Kim Zimmerman <alan.zimm@gmail.com>
<br>
<b>Sent:</b> 18 May 2018 15:31<br>
<b>To:</b> Simon Peyton Jones <simonpj@microsoft.com><br>
<b>Cc:</b> ghc-devs <ghc-devs@haskell.org><br>
<b>Subject:</b> Re: TTG hsSyn for Batch and Interactive Parsing<o:p></o:p></span></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"><o:p> </o:p></p>
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<p class="MsoNormal">On 18 May 2018 at 16:13, Simon Peyton Jones <<a href="mailto:simonpj@microsoft.com" target="_blank">simonpj@microsoft.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">We can’t make the result type depend on DynFlags! (Yet)(<o:p></o:p></p>
<p class="m5727447764977688943code"><b> parser :: DynFlags -> String </b><o:p></o:p></p>
<p class="m5727447764977688943code"><b> -> HsSyn (GhcPass (Parsed (if … </b><o:p></o:p></p>
<p class="m5727447764977688943code"><b> then WithApiAnnotations</b><o:p></o:p></p>
<p class="m5727447764977688943code"><b> else WihoutsApiAnnotations)</b><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">We could conceptually have<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"> parser :: DynFlags -> String -> Either (HsSyn (Parsed WithApiAnnotations)) (HsSyn (Parsed NoApiAnnotations))<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">The main point is that the next phase can make use of either of the variants.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">And it may be simplest to just always use the annotations, the ParsedSource is normally discarded after renaming 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">Alan<o:p></o:p></p>
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