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
|
--!A cross-platform build utility based on Lua
--
-- Licensed under the Apache License, Version 2.0 (the "License");
-- you may not use this file except in compliance with the License.
-- You may obtain a copy of the License at
--
-- http://www.apache.org/licenses/LICENSE-2.0
--
-- Unless required by applicable law or agreed to in writing, software
-- distributed under the License is distributed on an "AS IS" BASIS,
-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-- See the License for the specific language governing permissions and
-- limitations under the License.
--
-- Copyright (C) 2015-present, Xmake Open Source Community.
--
-- @author ruki
-- @file irpairs.lua
--
-- load modules
local table = require("base/table")
-- irpairs
--
-- e.g.
--
-- @code
--
-- for idx, val in irpairs({"a", "b", "c", "d", "e", "f"}) do
-- print("%d %s", idx, val)
-- end
--
-- for idx, val in irpairs({"a", "b", "c", "d", "e", "f"}, function (v) return v:upper() end) do
-- print("%d %s", idx, val)
-- end
--
-- for idx, val in irpairs({"a", "b", "c", "d", "e", "f"}, function (v, a, b) return v:upper() .. a .. b end, "a", "b") do
-- print("%d %s", idx, val)
-- end
--
-- @endcode
--
-- Implemented as a stateful closure so the loop body can safely
-- reassign the first loop variable under lua 5.4+ (paired with the
-- RDKCONST->VDKREG compile-time patch in core/src/lua/xmake.lua).
function sandbox_irpairs(t, filter, ...)
-- has filter?
local has_filter = type(filter) == "function"
-- stateful closure: keep the index in an upvalue so the loop body
-- can safely reassign the first loop variable (lua 5.4+ merges the
-- for-in control slot with the first user variable).
local args = table.pack(...)
t = table.wrap(t)
local i = table.getn(t) + 1
return function ()
i = i - 1
local v = t[i]
if v ~= nil then
if has_filter then
v = filter(v, table.unpack(args, 1, args.n))
end
return i, v
end
end
end
-- load module
return sandbox_irpairs
|
