PrintOptions for lists

[vrom911]

Bool to indicate whether to print list elements each on a separate line or all together (current version)

See use-case: kowainik/life-sync#102 (comment)

[willbasky]

@vrom911 Hi!
Could you clarify what list the task related ? I mean how what type in tomland and how it will look like with and without flag in toml file?

[vrom911]

@willbasky , sure!
I was thinking of patching the PrintOptions data type:

tomland/src/Toml/Type/Printer.hs

Lines 45 to 57 in 080e672

	data PrintOptions = PrintOptions
	{ {- | How table keys should be sorted, if at all.
	@since 1.1.0.0
	-}
	printOptionsSorting :: !(Maybe (Key -> Key -> Ordering))
	{- | Number of spaces by which to indent.
	@since 1.1.0.0
	-}
	, printOptionsIndent :: !Int
	}

by adding an additional field in there. That field should indicate how to pretty-print list types. Now, it would print all array elements in one line:

tomland/src/Toml/Type/Printer.hs

Line 146 in 080e672

valText (Array a) = "[" <> Text.intercalate ", " (map valText a) <> "]"

But with this change, lists should be outputted either like this:

foo = 
    [ a
    , b
    ]

or as before:

foo = [a, b]