clean up ast2pt
factorizing ast2pt
ready for upgrade
hackish way to workaround loc problem, reasons against ref:1. slow, 2.(a->loc) ref typing problem
Merge branch 'loc_bug_fix'
upgraded open -- parser change soon
add open!, let open! support now
inconsistent interface
clean
cut the dependency gstructure on FAstN
clean
separate treeparser seems to be successful