Minor refactor

src/GEval/BLEU.hs

@@ -55,11 +55,6 @@ precisionCount refs = sum . map (lookFor refs) . MS.toOccurList . MS.fromList
 upToTetragrams :: [a] -> ([a], [(a, a)], [(a, a, a)], [(a, a, a, a)])
 upToTetragrams l = (l, bigrams l, trigrams l, tetragrams l)
 
-bigrams :: [a] -> [(a, a)]
-bigrams [] = []
-bigrams [_] = []
-bigrams u = zip u $ tail u
-
 trigrams :: [a] -> [(a, a, a)]
 trigrams [] = []
 trigrams [_] = []

src/GEval/Common.hs

@@ -53,3 +53,8 @@ whitespace = many1 (satisfy isHorizontalSpace)
 indicator :: Bool -> Double
 indicator True = 1.0
 indicator False = 0.0
+
+bigrams :: [a] -> [(a, a)]
+bigrams [] = []
+bigrams [_] = []
+bigrams u = zip u $ tail u