1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
|
module TextBuilderDev.Isomorphic where
import qualified Data.Text.Lazy as TextLazy
import qualified Data.Text.Lazy.Builder as TextLazyBuilder
import TextBuilder
import TextBuilderDev.Prelude
-- |
-- Evidence that there exists an unambiguous way to convert
-- a type to and from "TextBuilder".
--
-- The laws are:
--
-- - @'from' . 'to' = 'id'@
--
-- - @'to' . 'from' = 'id'@
--
-- This class does not provide implicit rendering,
-- such as from integer to its decimal representation.
-- There are multiple ways of representing an integer
-- as text (e.g., hexadecimal, binary).
-- The non-ambiguity is further enforced by the presence of
-- the inverse conversion.
-- In the integer case there is no way to read it
-- from a textual form without a possibility of failing
-- (e.g., when the input string cannot be parsed as an integer).
class Isomorphic a where
-- | Project the type into "TextBuilder".
from :: a -> TextBuilder
-- | Embed "TextBuilder" into the type.
to :: TextBuilder -> a
instance Isomorphic TextBuilder where
from = id
to = id
instance Isomorphic Text where
from = text
to = toText
instance Isomorphic TextLazy.Text where
from = lazyText
to = TextLazy.fromStrict . toText
instance Isomorphic TextLazyBuilder.Builder where
from = lazyText . TextLazyBuilder.toLazyText
to = TextLazyBuilder.fromText . toText
|
