Re: Re-requiring modules

[Finn Wilcox <finnw@...>]

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On 22/10/2013 23:53, Robert Virding wrote:
> Yes, BUT NO. Well it shouldn't work. In the 5.2 manual description
> of package.loaded it says
> 
> "package.loaded
> 
> A table used by require to control which modules are already
> loaded. When you require a module modname and
> package.loaded[modname] is not false, require simply returns the
> value stored there.
> 
> This variable is only a reference to the real table; assignments to
> this variable do not change the table used by require."
> 
> Which seems to imply that these suggestions should not work. This
> is why I was asking as otherwise it is easy.

Assigning to "package.loaded[x]" - works (because the table you are
modifying is the same one that really is used to look up package names)

Assigning to "package.loaded", (i.e. attempting to replace the table)
does not work (because there are hidden references to the table, in
the registry and/or upvalues of C functions, and 'require' will
continue to use this table and not the one that you provide.

This is the case in the latest Lua 5.1 and 5.2, LuaJIT 2.0 and 2.1
(though they use different methods to find the table.)


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