在不进行“调用"的情况下将表值作为函数参数传递给Lua 4.功能 [英] Passing table values as function arguments in Lua 4 without the "call" function

问题描述

我有一个原则上可以是任意长度的值表:

I have a table of values that can in principle be of any length:

Points =
{
    "Point #1",
    "Point #5",
    "Point #7",
    "Point #10",
    "Point #5",
    "Point #11",
    "Point #5",
}

我想将它们作为参数传递给函数.

I want to pass them as arguments to a function.

addPath(<sPathName>, <sPoint>, <sPoint>, ...)

现在，通常可以使用通话"功能.但是在我正在使用的软件中，此功能不可用，不在范围内.

Now, normally you could use the "call" function. But in the software I am using this function is unavailable and not in scope.

如何在Lua 4中解决此问题?

How do I get around this problem in Lua 4?

此处是我可以使用的功能

推荐答案

在较新版本的Lua中，您将使用unpack，就像在addPath(sPathName,unpack(Points))中一样，但是Lua 4.0没有unpack.

In newer versions of Lua, you'd use unpack, as in addPath(sPathName,unpack(Points)), but Lua 4.0 does not have unpack.

如果您可以添加C代码，则Lua 5.0中的unpack在4.0中可以正常工作:

If you can add C code, unpack from Lua 5.0 works fine in 4.0:

static int luaB_unpack (lua_State *L) {
  int n, i;
  luaL_checktype(L, 1, LUA_TTABLE);
  n = lua_getn(L, 1);
  luaL_checkstack(L, n, "table too big to unpack");
  for (i=1; i<=n; i++)  /* push arg[1...n] */
    lua_rawgeti(L, 1, i);
  return n;
}

将此添加到lbaselib.c并将其添加到base_funcs:

Add this to lbaselib.c and this to base_funcs:

  {"unpack", luaB_unpack},

如果您无法添加C代码，那么您很不走运，并且很可能沦为这种黑客:

If you cannot add C code, then you're out of luck and are probably reduced to this hack:

function unpack(t)
  return t[1],t[2],t[3],t[4],t[5],t[6],t[7],t[8],t[9],t[10]
end

根据需要扩展return表达式，但是您最多只能输入200个左右.希望addPath忽略或在第一个nil处停止.

Extend the return expression as needed but you may only go as far as 200 or so. Let's hope that addPath ignores or stops at the first nil.

您也可以尝试使用此方法，它在第一个nil处停止，但没有明确的限制(有递归限制，最多只能处理250个表条目):

You can also try this one, which stops at the first nil but has no explicit limits (there are recursion limits and it'll only handle up to 250 table entries):

function unpack(t,i)
        i = i or 1
        if t[i]~=nil then
                return t[i],unpack(t,i+1)
        end
end

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