quebex

 1-- SPDX-FileCopyrightText: 2025 Sören Tempel <soeren+git@soeren-tempel.net>
 2--
 3-- SPDX-License-Identifier: GPL-3.0-only
 4{-# OPTIONS_GHC -Wno-x-partial #-}
 5
 6module Language.QBE.Util where
 7
 8import Data.Word (Word64)
 9import Language.QBE.Numbers
10  ( decimal,
11    fractExponent,
12    hexnum,
13    octnum,
14    sign,
15  )
16import Text.ParserCombinators.Parsec
17  ( Parser,
18    char,
19    oneOf,
20    skipMany,
21    string,
22    (<|>),
23  )
24
25bind :: String -> a -> Parser a
26bind str val = val <$ string str
27
28decNumber :: Parser Word64
29decNumber = do
30  -- TODO: QBE probably doesn't support a '+' sign prefix
31  s <- sign
32  s <$> decimal
33
34octNumber :: Parser Word64
35octNumber = do
36  char '0' >> octnum
37
38-- A float parser that tries to be compatible with strtod(3).
39float :: (Floating f, Read f) => Parser f
40float = do
41  _ <- skipSpace
42  s <- sign
43  -- TODO: Support infininty and NaN
44  (decimal <|> hexnum) >>= fractExponent . s
45  where
46    -- See musl's isspace(3) implementation.
47    skipSpace :: Parser ()
48    skipSpace = skipMany $ oneOf " \t\n\v\f\r"