File size: 1,945 Bytes
d7c5875 | 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 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 | local lua_version = _VERSION:sub(-3)
local M = {}
local unpack = lua_version == "5.1" and unpack or table.unpack
local function addasterisk(fmt)
if type(fmt) == "string" and fmt:sub(1, 1) ~= "*" then
return "*"..fmt
else
return fmt
end
end
function M.update_file_meta(file_meta, is_luajit52)
-- make '*' optional for file:read and file:lines
local file_lines = file_meta.__index.lines
file_meta.__index.lines = function(self, ...)
local n = select('#', ...)
for i = 1, n do
local a = select(i, ...)
local b = addasterisk(a)
-- as an optimization we only allocate a table for the
-- modified format arguments when we have a '*' somewhere
if a ~= b then
local args = { ... }
args[i] = b
for j = i+1, n do
args[j] = addasterisk(args[j])
end
return file_lines(self, unpack(args, 1, n))
end
end
return file_lines(self, ...)
end
local file_read = file_meta.__index.read
file_meta.__index.read = function(self, ...)
local n = select('#', ...)
for i = 1, n do
local a = select(i, ...)
local b = addasterisk(a)
-- as an optimization we only allocate a table for the
-- modified format arguments when we have a '*' somewhere
if a ~= b then
local args = { ... }
args[i] = b
for j = i+1, n do
args[j] = addasterisk(args[j])
end
return file_read(self, unpack(args, 1, n))
end
end
return file_read(self, ...)
end
if not is_luajit52 then
local file_write = file_meta.__index.write
file_meta.__index.write = function(self, ...)
local ret, err = file_write(self, ...)
if ret then
return self
end
return ret, err
end
end
end
return M
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