Add typed hole example to GHC-88464 #549
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BinderDavid
approved these changes
Nov 2, 2024
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Thanks for maintaining this project! The more of these random bits of wisdom it accumulates, the more useful it gets. |
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GHC considers typed holes to be variables that are out of scope, but with special handling in the diagnostics. (Apparently.) So typed holes have the same error number as out-of-scope variables, even though they arise in (from the programmer's perspective) quite different situations.
This adds a simple example and some text explaining how typed holes can be useful.