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I see SPJ's point, but he makes another point in the same video, which is that Haskell has a small, internal core language to which everything must elaborate, so this would seem to make formalization even more attractive: formalize and prove safety for the
core language once and for all, and then specify the elaborations and check their properties modularly, which should work well even in the face of language evolution.<o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:12.0pt">Yes – and Core is indeed formalised quite carefully (by Richard Eisenberg). See
<a href="https://ghc.haskell.org/trac/ghc/ticket/14572#comment:8">https://ghc.haskell.org/trac/ghc/ticket/14572#comment:8</a>
<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt">Simon<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"> Haskell-Cafe [mailto:haskell-cafe-bounces@haskell.org]
<b>On Behalf Of </b>Todd Wilson<br>
<b>Sent:</b> 17 December 2017 19:53<br>
<b>To:</b> Haskell Cafe <haskell-cafe@haskell.org><br>
<b>Subject:</b> Re: [Haskell-cafe] The Definition of Haskell<o:p></o:p></span></p>
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On Sat, Dec 16, 2017 at 9:14 PM Brandon Allbery <<a href="mailto:allbery.b@gmail.com">allbery.b@gmail.com</a>> wrote:<o:p></o:p></p>
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Dunno about safety results, but <a href="https://www.haskell.org/onlinereport/haskell2010/" target="_blank">https://www.haskell.org/onlinereport/haskell2010/</a> exists (next revision expected in 2020 iirc).<o:p></o:p></p>
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Although this can be considered a definition of the language, it is by no means a formal definition of the static and dynamic semantics of the language in a form amenable to representation in systems like Coq, where metatheory might be checked.<o:p></o:p></p>
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On Sat, Dec 16, 2017 at 9:22 PM Baojun Wang <<a href="mailto:wangbj@gmail.com">wangbj@gmail.com</a>> wrote:<o:p></o:p></p>
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SPJ may answered part of it in his talk Escape from the ivory tower: <a href="https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3Dre96UgMk6GQ%26feature%3Dshare&data=02%7C01%7Csimonpj%40microsoft.com%7C6fb497b3f6c94c81876e08d545882101%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636491373335007410&sdata=5WnVwESDGAotRmeUq6wevSmwgsg6hFFGe6c90YYFv6E%3D&reserved=0" target="_blank">https://www.youtube.com/watch?v=re96UgMk6GQ&feature=share</a> from
about 29 minutes.<o:p></o:p></p>
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<o:p> </o:p></p>
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Nice talk; thanks for the reference. To summarize: formalization, which is a lot of work, leads to standardization and the reluctance to change the language, and one of Haskell's strong points is that it is constantly evolving.<o:p></o:p></p>
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I see SPJ's point, but he makes another point in the same video, which is that Haskell has a small, internal core language to which everything must elaborate, so this would seem to make formalization even more attractive: formalize and prove safety for the
core language once and for all, and then specify the elaborations and check their properties modularly, which should work well even in the face of language evolution.<o:p></o:p></p>
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