Implement stimes for Doc (#135)

Fixes #133.
quchen · Jun 30, 2020 · fbbc66e · fbbc66e
1 parent 9635a5d
commit fbbc66e
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Showing 3 changed files with 23 additions and 1 deletion.
diff --git a/prettyprinter/prettyprinter.cabal b/prettyprinter/prettyprinter.cabal
@@ -65,7 +65,7 @@ library
     if impl(ghc >= 8.0)
         ghc-options: -Wcompat
     if !impl(ghc >= 8.0)
-        build-depends: semigroups >= 0.16.1
+        build-depends: semigroups >= 0.17
         build-depends: fail >= 4.9.0.0 && <4.10
     if !impl(ghc >= 7.10)
         build-depends: void >=0.4 && <0.8

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -203,6 +203,26 @@ data Doc ann =
 instance Semigroup (Doc ann) where
     (<>) = Cat
     sconcat (x :| xs) = hcat (x:xs)
+    stimes n x
+      | n <= 0    = Empty
+      | n == 1    = x
+      | otherwise =
+          let n' = fromIntegral n
+              nx = hcat (replicate n' x)
+          in case x of
+              Fail            -> Fail
+              Empty           -> Empty
+              Char c          -> Text n' (T.replicate n' (T.singleton c))
+              Text l t        -> Text (n' * l) (T.replicate n' t)
+              Line            -> nx
+              FlatAlt{}       -> nx
+              Cat{}           -> nx
+              Nest{}          -> nx
+              Union{}         -> nx
+              Column{}        -> nx
+              WithPageWidth{} -> nx
+              Nesting{}       -> nx
+              Annotated{}     -> nx
 
 -- |
 -- @

diff --git a/stack-older-snapshots.yaml b/stack-older-snapshots.yaml
@@ -10,5 +10,7 @@ extra-deps:
     - pgp-wordlist-0.1.0.2
     - ansi-wl-pprint-0.6.8
     - fail-4.9.0.0
+    - semigroups-0.17.0.1
+    - void-0.7.3
 flags: {}
 extra-package-dbs: []