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Diffstat (limited to 'ghc/compiler/utils/Util.lhs')
| -rw-r--r-- | ghc/compiler/utils/Util.lhs | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/ghc/compiler/utils/Util.lhs b/ghc/compiler/utils/Util.lhs index b16f6eb969..0911dba841 100644 --- a/ghc/compiler/utils/Util.lhs +++ b/ghc/compiler/utils/Util.lhs @@ -13,7 +13,7 @@ module Util ( mapAndUnzip, mapAndUnzip3, nOfThem, filterOut, lengthExceeds, lengthIs, lengthAtLeast, listLengthCmp, atLength, - isSingleton, only, + isSingleton, only, singleton, notNull, snocView, isIn, isn'tIn, @@ -299,6 +299,9 @@ listLengthCmp = atLength atLen atEnd atLen [] = EQ atLen _ = GT +singleton :: a -> [a] +singleton x = [x] + isSingleton :: [a] -> Bool isSingleton [x] = True isSingleton _ = False |