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063d4e4543
This is the first commit for the branch Lua 5.3. All source files were copied from the official distribution of 5.3.5 in the Lua site. The test files are the same of 5.3.4. The manual came from the previous RCS repository, revision 1.167.1.2.
79 lines
1.7 KiB
Lua
79 lines
1.7 KiB
Lua
local tonumber, tointeger = tonumber, math.tointeger
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local type, getmetatable, rawget, error = type, getmetatable, rawget, error
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local strsub = string.sub
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local print = print
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_ENV = nil
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-- Try to convert a value to an integer, without assuming any coercion.
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local function toint (x)
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x = tonumber(x) -- handle numerical strings
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if not x then
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return false -- not coercible to a number
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end
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return tointeger(x)
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end
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-- If operation fails, maybe second operand has a metamethod that should
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-- have been called if not for this string metamethod, so try to
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-- call it.
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local function trymt (x, y, mtname)
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if type(y) ~= "string" then -- avoid recalling original metamethod
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local mt = getmetatable(y)
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local mm = mt and rawget(mt, mtname)
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if mm then
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return mm(x, y)
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end
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end
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-- if any test fails, there is no other metamethod to be called
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error("attempt to '" .. strsub(mtname, 3) ..
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"' a " .. type(x) .. " with a " .. type(y), 4)
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end
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local function checkargs (x, y, mtname)
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local xi = toint(x)
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local yi = toint(y)
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if xi and yi then
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return xi, yi
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else
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return trymt(x, y, mtname), nil
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end
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end
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local smt = getmetatable("")
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smt.__band = function (x, y)
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local x, y = checkargs(x, y, "__band")
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return y and x & y or x
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end
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smt.__bor = function (x, y)
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local x, y = checkargs(x, y, "__bor")
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return y and x | y or x
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end
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smt.__bxor = function (x, y)
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local x, y = checkargs(x, y, "__bxor")
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return y and x ~ y or x
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end
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smt.__shl = function (x, y)
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local x, y = checkargs(x, y, "__shl")
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return y and x << y or x
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end
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smt.__shr = function (x, y)
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local x, y = checkargs(x, y, "__shr")
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return y and x >> y or x
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end
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smt.__bnot = function (x)
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local x, y = checkargs(x, x, "__bnot")
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return y and ~x or x
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end
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