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authorNadrieril2019-05-07 18:12:04 +0200
committerNadrieril2019-05-07 18:12:04 +0200
commit3da450aa3fae23214aa982643b9bc4dd0ea4eaa6 (patch)
tree02e00cd008d2e7dc899b9211379596fe792f41c8 /dhall/src/error/text/HandlerNotAFunction.txt
parentd8a3e831fb67f86269c4baa99f9f0798a73a7247 (diff)
parent14dfeb8e7d2aa87a361a711a485243449426b144 (diff)
Merge branch 'reorganize'
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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