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Explanation: You can ❰merge❱ the alternatives of a union using a record with one
handler per alternative, like this:
┌─────────────────────────────────────────────────────────────────────┐
│ let union = < Left = +2 | Right : Bool > │
│ in let handlers = { Left = Natural/even, Right = λ(x : Bool) → x } │
│ in merge handlers union : Bool │
└─────────────────────────────────────────────────────────────────────┘
... as long as each handler is a function
For example, the following expression is $_NOT valid:
┌─────────────────────────────────────────┐
│ merge { Foo = True } < Foo = 1 > : Bool │
└─────────────────────────────────────────┘
⇧
Invalid: Not a function
Your handler for this alternative:
↳ $txt0
... has the following type:
↳ $txt1
... which is not the type of a function
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