propellor/src/Utility/Table.hs

30 lines
864 B
Haskell

{- text based table generation
-
- Copyright 2014 Joey Hess <id@joeyh.name>
-
- License: BSD-2-clause
-}
module Utility.Table where
type Table = [[String]]
-- | A table with a header that is set off with lines under each
-- header item.
tableWithHeader :: [String] -> [[String]] -> Table
tableWithHeader header rows = header : map linesep header : rows
where
linesep = map (const '-')
-- | Formats a table to lines, automatically padding columns to the same size.
formatTable :: Table -> [String]
formatTable table = map (\r -> unwords (map pad (zip r colsizes))) table
where
pad (cell, size) = cell ++ take (size - length cell) padding
padding = repeat ' '
colsizes = reverse $ (0:) $ drop 1 $ reverse $
sumcols (map (map length) table)
sumcols [] = repeat 0
sumcols [r] = r
sumcols (r1:r2:rs) = sumcols $ map (uncurry max) (zip r1 r2) : rs