1  XML:
 2  ====
 3    - I/O avoid copies when parsing mmap'ed files, need to use
 4      unmutable buffers except for the last 4K to make it 0 terminated
 5      (or get rid of 0 termination check in the whole parser, hard !)
 6    - recheck > 4Gb instances for parsing, and RNG validation.
 7      
 8  
 9  XSLT:
10  =====
11    - global variable access
12       for each expr in stylesheet : allocate index
13       for each transformation context
14         create an index table
15           cache values in the transformation
16  	   - context evaluation
17  	     - cache
18  	     - constants at the XPAth level
19  	   - provide more info on compiled expressions
20  	     - dependances w.r.t. variables (which ones)
21  	     - dependancy on the current node
22  	     - dependancy on the current document
23    - do not use _private but other fields in the node structures.