Add a missing case to the lambda lifting transformation - #6093
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The encloser was not keeping track of the fact that `x` in
x = <binding>
<body>
will not be floated, and will shadow let-rec variables in <body>,
so we need to remove `x` from the variables to avoid enclosing.
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Nice |
aryairani
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Jan 7, 2026
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passed CI with moderate effort 💪
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This PR fixes an oversight in the lambda lifter.
The first step of the process is to enclose terms that will be floated, so that they take their local references as arguments. We avoid adding arguments for references that will become part of the overall let-rec. However, this step was missing that lets could shadow the let-rec variables, so it would avoid enclosing these shadowing variables.
For instance, in code of the form
barwould not havefooenclosed, even though itsfooreference is the inner one, not the top level.Fixes #5889, which was caused by the test using a
resultvariable, and the test process tweaking the code to useresultto refer to the overall test result (I think).