Re: [wxlua-users] wxLua users please comment : Do we want stricter type checking?

[Hakki D. <dog...@tr...>]

Hi,

John Labenski wrote:
> First off, I'm going to rename some rather unfortunately named
> functions. These are mostly internal to wxLua, but you may have to
> rebuild your bindings using genwxbind.lua.
> 
> More importantly, do we want stricter function parameter type
> checking. Lua itself is very generous and will convert numbers to
> strings, nil to number, etc... BUT, this means that without some
> checking you can spend a lot of time debugging a small typo since vars
> can be created on the fly with the value nil.
> 
> Lua has nice functions, tostring(X), tonumber(X), and nil can be
> avoided using "nil or value".
> 
> Below is what we currently accept for different variable types and
> what I propose I marked with a *
> 
> See here
> http://wxlua.cvs.sourceforge.net/wxlua/wxLua/modules/wxlua/src/wxlstate.cpp?view=markup
> 
> wxLua_lua_isstringtype
>         case LUA_TNIL:          * MAKE INVALID can use [str or ""]

Ok.

>         case LUA_TSTRING:
>         case LUA_TNUMBER: // can convert easily
> 
> wxLua_lua_isbooleantype
>        case LUA_TNIL:
>        case LUA_TNUMBER:
>        case LUA_TBOOLEAN:
> 
> wxLua_lua_isenumerationtype
>       case LUA_TNUMBER  * check to see if it's an INT? probably not

If you can't check that it is really an enum value, why bother?
wx itself accepts int for enum? ex:
// Bitmap flags
enum wxBitmapType
{
     wxBITMAP_TYPE_INVALID,          // should be == 0 for compatibility!
     wxBITMAP_TYPE_BMP,
     wxBITMAP_TYPE_BMP_RESOURCE,
...
     wxBITMAP_TYPE_ANY = 50
};

wxImage(const wxString& name, long type = wxBITMAP_TYPE_ANY, int index = -1)

> 
> wxLua_lua_isnumbertype
>         case LUA_TNIL:          * MAKE INVALID can use [num or 0]

Ok.

>         //case LUA_TSTRING: // will be 0 unless really a number "2"
>         case LUA_TNUMBER:
>         case LUA_TBOOLEAN:
> 
> Thoughts?
>      John Labenski
> 


--
Regards,
Hakki Dogusan