Editing Module:Buffer/doc (section)

====Buffer:_B====

{{luaself|:_B|args=var}}

Takes only one argument and returns that argument.

Assuming the only ''X'' declared is {{luaref|_G|_G.X}} and new_G equals _G, then {{luaself|:_B|args=(X)}} and {{luaself|:_2|args='X'}} are equivalent.<ref group=note>Dubbing this a "global function" is bit of a misnomer since this never retrieves anything from the global table. While designed for in-chain navigation to Buffer objects that were [[#Buffer:_G|self-declared as globals]], this returns any local reference or literal passed as well (allowing {{luaself|pre=Element-|:_add}} to execute Buffer methods on non-Buffer objects <code>[[#args.globalFunction|args._B]]</code>).</ref>

When passed a variable that does not exist, this returns the Buffer nil object:

{{anchor|Buffer-nil}}
=====Buffer-nil object=====
{{luaself|\-nil()}}

{{luaself|\-nil:anyName|args=():_B( var )}}

The Buffer-nil object is unique. Calling this as a function returns nothing (in contrast, calling an empty Buffer object returns an empty string). This does however have the Module:Buffer __concat metamethod, which treats this the same way as any [[#invalid|invalid]] object (i.e. ignores it).

Appending this via {{luaref|mw.html:node}} or {{luaself|:_}} has the same effect as appending nil. Passing this to {{luaref|tostring||y}} returns nil instead of the string 'nil'.

The only real Buffer method in its meta __index is {{luaself|:_B}}, however, any non-numerical key string retrieves a function that only returns the Buffer nil object for call chaining. In a sense, you can think of {{code|lang=lua|Buffer:_B(var):...}} as an {{code|lang=lua|1=if var~=nil then var:...}} block around the following chain that ends in the next :_B().

If {{luaref|mw.clone|cloned|y}}, the clone will be a normal Buffer object.

{{anchor|_G object}}<!--anchor below excludes the _ -->