Wingman: Don't clobber where clauses #2184
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santiweight
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Sep 10, 2021
| -- It's important that there is no where clause because otherwise it gets | ||
| -- clobbered. See #2183 for an example. | ||
| -- | ||
| -- This isn't a perfect check, and produces some ugly code. But it's much much |
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In what way is this not a perfect check? I don't quite catch your meaning here.
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I also don't quite understand why this produces ugly code.
jneira
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Sep 13, 2021
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Sep 14, 2021
* Extend TopLevelRHS pattern to track the where clause * Don't case split if there's a where clause * Add tests Co-authored-by: Javier Neira <atreyu.bbb@gmail.com>
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Wingman generates lambdas and case expressions by default. When it thinks it's operating over a top-level hole, it will instead replace the entire match group, by desugaring the lambdas and cases into explicit matches. This works fine unless there's a
whereattached to the original match group --- in which case it gets clobbered.This PR prevents the match-group splicing behavior if there's a
whereattached to the hole. It's not the world's best fix, but it's a quick fix. The bug is pretty destructive so I'd rather get it fixed quickly than perfectly. And it's not clear what a perfect solution would look like here.Fixes #2183