Pointer on a document (suite)

FROM : Eric PETIT
DATE : Sat Jan 19 22:11:24 2008

I am trying to achieve the following thing :
In a class, I want to create a document and "write" NSString with the 
"insertText" method.
I create this document with : [NSApp sendAction:@selector
(newDocument:) to:nil from:self] but to use "insertText" on it, I 
need to recover a pointer on the created document.
How can I recover the pointer on the document created with [NSApp 
sendAction:@selector(newDocument:) to:nil from:self] ?

Eric PETIT