[project @ 1997-03-14 07:52:06 by simonpj]

[ghc-hetmet.git] / ghc / lib / tests / Array / arr002 / Main.hs

diff --git a/ghc/lib/tests/Array/arr002/Main.hs b/ghc/lib/tests/Array/arr002/Main.hs
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+-- Array creation, (index,value) list with duplicates.
+-- 
+-- Haskell library report 1.3 (and earlier) specifies
+-- that `array' values created with lists containing dups,
+-- are undefined ( _|_ ).
+--
+-- GHC-2.02 (and earlier) does not flag this as such, the
+-- last (index,value) is instead used.
+--
+-- The report also specifies `array' is spine strict in
+-- the (index,value) list argument and to check the
+-- validity of the index values upon creation, it also
+-- strict for the indices. To test this, we do (a!1)
+-- twice, expecting to see the same value..
+--
+import Array
+
+main =
+ let a1 = array (1,3) (zip (1:[1..3]) ['a'..'d']) in
+ print (a1!1) >>
+ print a1     >>
+ print (a1!1)
+