From 14c8fc3768d978205bf17ffc1905c2772afbd434 Mon Sep 17 00:00:00 2001 From: Nat Goodspeed Date: Wed, 28 Aug 2024 16:47:38 -0400 Subject: Add `LL.setdtor()` function to add a "destructor" to any Lua object. `setdtor('description', object, function)` returns a proxy userdata object referencing object and function. When the proxy is garbage-collected, or at the end of the script, its destructor calls `function(object)`. The original object may be retrieved as `proxy._target`, e.g. to pass it to the `table` library. The proxy also has a metatable with metamethods supporting arithmetic operations, string concatenation, length and table indexing. For other operations, retrieve `proxy._target`. (But don't assign to `proxy._target`. It will appear to work, in that subsequent references to `proxy._target` will retrieve the replacement object -- however, the destructor will still call `function(original object)`.) Fix bugs in `lua_setfieldv()`, `lua_rawgetfield()` and `lua_rawsetfield()`. Add C++ functions `lua_destroyuserdata()` to explicitly destroy a `lua_emplace()` userdata object, plus `lua_destroybounduserdata()`. The latter can bind such a userdata object as an upvalue to pass to `LL.atexit()`. Make `LL.help()` and `LL.leaphelp()` help text include the `LL.` prefix. --- indra/newview/scripts/lua/test_setdtor.lua | 62 ++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 indra/newview/scripts/lua/test_setdtor.lua (limited to 'indra/newview/scripts/lua') diff --git a/indra/newview/scripts/lua/test_setdtor.lua b/indra/newview/scripts/lua/test_setdtor.lua new file mode 100644 index 0000000000..743c5168d0 --- /dev/null +++ b/indra/newview/scripts/lua/test_setdtor.lua @@ -0,0 +1,62 @@ +inspect = require 'inspect' + +print('initial setdtor') +bye = LL.setdtor('initial setdtor', 'Goodbye world!', print) + +print('arithmetic') +n = LL.setdtor('arithmetic', 11, print) +print("n =", n) +print("n._target =", n._target) +print("getmetatable(n) =", inspect(getmetatable(n))) +print("-n =", -n) +for i = 10, 12 do + -- Comparison metamethods are only called if both operands have the same + -- metamethod. + tempi = LL.setdtor('tempi', i, function(n) print('temp', i) end) + print(`n < {i}`, n < tempi) + print(`n <= {i}`, n <= tempi) + print(`n == {i}`, n == tempi) + print(`n ~= {i}`, n ~= tempi) + print(`n >= {i}`, n >= tempi) + print(`n > {i}`, n > tempi) +end +for i = 2, 3 do + print(`n + {i} =`, n + i) + print(`{i} + n =`, i + n) + print(`n - {i} =`, n - i) + print(`{i} - n =`, i - n) + print(`n * {i} =`, n * i) + print(`{i} * n =`, i * n) + print(`n / {i} =`, n / i) + print(`{i} / n =`, i / n) + print(`n % {i} =`, n % i) + print(`{i} % n =`, i % n) + print(`n ^ {i} =`, n ^ i) + print(`{i} ^ n =`, i ^ n) +end + +print('string') +s = LL.setdtor('string', 'hello', print) +print('s =', s) +print('#s =', #s) +print('s .. " world" =', s .. " world") +print('"world " .. s =', "world " .. s) + +print('table') +t = LL.setdtor('table', {'[1]', '[2]', abc='.abc', def='.def'}, + function(t) print(inspect(t)) end) +print('t =', inspect(t)) +print('t._target =', inspect(t._target)) +print('#t =', #t) +print('t[2] =', t[2]) +print('t.def =', t.def) +t[1] = 'new [1]' +print('t[1] =', t[1]) + +print('function') +f = LL.setdtor('function', function(a, b) return (a .. b) end, print) +print('f =', f) +print('f._target =', f._target) +print('f("Hello", " world") =', f("Hello", " world")) + +print('cleanup') -- cgit v1.2.3