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Edit PatternSynonyms authored by Matthew Pickering's avatar Matthew Pickering
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......@@ -728,9 +728,7 @@ Could you give examples ti illustrate the re-export thing? Which I do not under
**SLPJ** this second bullet does not seem to be part of the definition of "`M` exports `T` whilst associating `P`". Correct?
**MP** No, this second section describes the case when `T` is not defined in `M`. The first case solely concerns when `T`*is* defined in `M`.
- In the case of the abbreviated form `T(..)`, If `M` imports `T` from `N` then `T(..)` names the type and any constructors and field names which are in scope as well as any pattern synonyms (in scope) which are associated to `T` relative to `N`.
**MP** Ah, I see how Richard's edits seemed to have confused this a bit. I don't think it's necessary anymore.
#### Imports
......@@ -750,67 +748,26 @@ For any modules `M``N`, if we import `N` from `M`,
#### Examples
```wiki
module N(T(.., P)) where
data T = MkT Int
pattern P = MkT 5
-- M.hs
module M where
import N (T(..))
```
moduleN(T(..,P))wheredataT=MkTIntpatternP=MkT5-- M.hsmoduleMwhereimportN(T(..))
```
`P` is associated with `T` relative to `N`. M imports `T`, `MkT` and `P`.
```wiki
module N(T(..)) where
data T = MkT Int
pattern P = MkT 5
-- M.hs
module M where
import N (T(..))
```
moduleN(T(..))wheredataT=MkTIntpatternP=MkT5-- M.hsmoduleMwhereimportN(T(..))
```
`P` is unassociated. `M` imports `T` and `MkT`.
```wiki
module N(T(P)) where
data T = MkT Int
pattern P = MkT 5
-- M.hs
module M where
import N (T(..))
```
moduleN(T(P))wheredataT=MkTIntpatternP=MkT5-- M.hsmoduleMwhereimportN(T(..))
```
`P` is associated with `T` relative to `N`. M imports `T`, and `P`.
```wiki
module N(T(P)) where
data T = MkT Int
pattern P = MkT 5
-- M.hs
module M (T(..)) where
import N (T(..))
-- O.hs
module O where
import M (T(..))
```
moduleN(T(P))wheredataT=MkTIntpatternP=MkT5-- M.hsmoduleM(T(..))whereimportN(T(..))-- O.hsmoduleOwhereimportM(T(..))
```
`P` is associated with `T` relative to `N`.
......@@ -819,24 +776,10 @@ import M (T(..))
As `M` imports `N` and imports `T`, `P` is associated with `T` relative to `M`. Thus `M` exports `T` and `P`.
Therefore when `O` imports `T(..)` from `M`, it also imports `P`.
Therefore when `O` imports `T(..)` from `M`, it imports `T` and `P`.
```wiki
module N(T(..)) where
data T = MkT Int
-- M.hs
module M(T(P)) where
import N (T(..))
pattern P = MkT 5
-- O.hs
module O where
import M (T(..))
```
moduleN(T(..))wheredataT=MkTInt-- M.hsmoduleM(T(P))whereimportN(T(..))patternP=MkT5-- O.hsmoduleOwhereimportM(T(..))
```
......