[commit: ghc] master: Pretty: use replicate for spaces and multi_ch (#10735) (85179b5)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/85179b5821bb1010eede7cec43280c2cd7e59bd3/ghc

>---------------------------------------------------------------

commit 85179b5821bb1010eede7cec43280c2cd7e59bd3
Author: Thomas Miedema <thomasmiedema at gmail.com>
Date:   Tue Aug 4 18:32:09 2015 +0200

    Pretty: use replicate for spaces and multi_ch (#10735)
    
    Similar changes were made to pretty in commit
    7575ab16430c876eaa1451b02465b6b103b3a519.


>---------------------------------------------------------------

85179b5821bb1010eede7cec43280c2cd7e59bd3
 compiler/utils/Pretty.hs | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/compiler/utils/Pretty.hs b/compiler/utils/Pretty.hs
index 741c931..0bde5fa 100644
--- a/compiler/utils/Pretty.hs
+++ b/compiler/utils/Pretty.hs
@@ -430,8 +430,7 @@ isEmpty _     = False
 --
 -- an old version inserted tabs being 8 columns apart in the output.
 spaces :: Int -> String
-spaces !n | n <= 0    = ""
-          | otherwise = ' ' : spaces (n - 1)
+spaces !n = replicate n ' '
 
 {-
 Q: What is the reason for negative indentation (i.e. argument to indent
@@ -1000,13 +999,13 @@ display m !page_width !ribbon_width txt end doc
             = case m of
                     ZigZagMode |  k >= gap_width
                                -> nlText `txt` (
-                                  Str (multi_ch shift '/') `txt` (
+                                  Str (replicate shift '/') `txt` (
                                   nlText `txt`
                                   lay1 (k - shift) s sl p ))
 
                                |  k < 0
                                -> nlText `txt` (
-                                  Str (multi_ch shift '\\') `txt` (
+                                  Str (replicate shift '\\') `txt` (
                                   nlText `txt`
                                   lay1 (k + shift) s sl p ))
 
@@ -1037,10 +1036,6 @@ display m !page_width !ribbon_width txt end doc
     lay 0 doc
     }}
 
-multi_ch :: Int -> Char -> String
-multi_ch !n ch | n <= 0    = ""
-               | otherwise = ch : multi_ch (n - 1) ch
-
 printDoc :: Mode -> Int -> Handle -> Doc -> IO ()
 -- printDoc adds a newline to the end
 printDoc mode cols hdl doc = printDoc_ mode cols hdl (doc $$ text "")