swade-fr-content-neoflip/tools/luajson/json/decode/number.lua

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2021-03-17 17:45:57 +01:00
--[[
Licensed according to the included 'LICENSE' document
Author: Thomas Harning Jr <harningt@gmail.com>
]]
local lpeg = require("lpeg")
local tonumber = tonumber
local jsonutil = require("json.util")
local merge = jsonutil.merge
local util = require("json.decode.util")
local _ENV = nil
local digit = lpeg.R("09")
local digits = digit^1
-- Illegal octal declaration
local illegal_octal_detect = #(lpeg.P('0') * digits) * util.denied("Octal numbers")
local int = (lpeg.P('-') + 0) * (lpeg.R("19") * digits + illegal_octal_detect + digit)
local frac = lpeg.P('.') * digits
local exp = lpeg.S("Ee") * (lpeg.S("-+") + 0) * digits
local nan = lpeg.S("Nn") * lpeg.S("Aa") * lpeg.S("Nn")
local inf = lpeg.S("Ii") * lpeg.P("nfinity")
local ninf = lpeg.P('-') * lpeg.S("Ii") * lpeg.P("nfinity")
local hex = (lpeg.P("0x") + lpeg.P("0X")) * lpeg.R("09","AF","af")^1
local defaultOptions = {
nan = true,
inf = true,
frac = true,
exp = true,
hex = false
}
local modeOptions = {}
modeOptions.strict = {
nan = false,
inf = false
}
local nan_value = 0/0
local inf_value = 1/0
local ninf_value = -1/0
--[[
Options: configuration options for number rules
nan: match NaN
inf: match Infinity
frac: match fraction portion (.0)
exp: match exponent portion (e1)
DEFAULT: nan, inf, frac, exp
]]
local function mergeOptions(options, mode)
jsonutil.doOptionMerge(options, false, 'number', defaultOptions, mode and modeOptions[mode])
end
local function generateLexer(options)
options = options.number
local ret = int
if options.frac then
ret = ret * (frac + 0)
else
ret = ret * (#frac * util.denied("Fractions", "number.frac") + 0)
end
if options.exp then
ret = ret * (exp + 0)
else
ret = ret * (#exp * util.denied("Exponents", "number.exp") + 0)
end
if options.hex then
ret = hex + ret
else
ret = #hex * util.denied("Hexadecimal", "number.hex") + ret
end
-- Capture number now
ret = ret / tonumber
if options.nan then
ret = ret + nan / function() return nan_value end
else
ret = ret + #nan * util.denied("NaN", "number.nan")
end
if options.inf then
ret = ret + ninf / function() return ninf_value end + inf / function() return inf_value end
else
ret = ret + (#ninf + #inf) * util.denied("+/-Inf", "number.inf")
end
return ret
end
local number = {
int = int,
mergeOptions = mergeOptions,
generateLexer = generateLexer
}
return number