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author | NanoTech | 2016-12-11 23:27:36 -0600 |
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committer | NanoTech | 2017-03-10 23:48:29 -0600 |
commit | 5c00b978b0bc0c1eeb64682cba6aa338fea320bf (patch) | |
tree | d9935794062180474b5bd6a51ab1d5f4bd864a4e /src/errors/NoDependentTypes.txt | |
parent | efd52ef33c15316dbd39390d55022708488a53b8 (diff) |
Start implementing error explanations
Diffstat (limited to 'src/errors/NoDependentTypes.txt')
-rw-r--r-- | src/errors/NoDependentTypes.txt | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/src/errors/NoDependentTypes.txt b/src/errors/NoDependentTypes.txt new file mode 100644 index 0000000..435bdcb --- /dev/null +++ b/src/errors/NoDependentTypes.txt @@ -0,0 +1,31 @@ +Explanation: The Dhall programming language does not allow functions from terms +to types. These function types are also known as "dependent function types" +because you have a type whose value "depends" on the value of a term. + +For example, this is $_NOT a legal function type: + + + ┌─────────────┐ + │ Bool → Type │ + └─────────────┘ + + +Similarly, this is $_NOT legal code: + + + ┌────────────────────────────────────────────────────┐ + │ λ(Vector : Natural → Type → Type) → Vector +0 Text │ + └────────────────────────────────────────────────────┘ + ⇧ + Invalid dependent type + + +Your function type is invalid because the input has type: + +↳ $txt0 + +... and the output has kind: + +↳ $txt1 + +... which makes this a forbidden dependent function type |