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A comment on Expresso: A simple expressions language with polymorphic extensible row types. Parent comment

Re:Expresso: A simple expressions language with polymorphic ... by willtim on Sunday November 18, 2018 @04:12AM (#18479496)
Labels in Expresso are just type-level symbols. Label names can be re-used over and over again in different records and variants. This works fine because a name is not tired to any particular nominal type (like a constructor in Haskell or Java).
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Re:Expresso: A simple expressions language with polymorphic ... by acjohnson55 on Tuesday November 20, 2018 @09:36PM (#18499784)
But it seems like it would be an error to concatenate two records with a name clash, though, right?
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Re:Expresso: A simple expressions language with polymorphic ... by willtim on Friday November 30, 2018 @02:40AM (#18567436)
Yes because duplicate labels are not allowed within the scope of a single record (you can specify which one overrides the other, but perhaps we also need a convenient rename syntax). This point was that different records can happily contain the same field names. The situation is the same as SQL.
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