s/@/ATSIGN/g
s/^/@/
s/$/@/
s/[^A-Za-z0-9_]\+/@&@/g

s/@\(TNULL\)[01]@/@\1@/g
s/@\(union@[	 ]*@tree\)[01]@/@\1@/g
s/@\(struct@[	 ]*@tnode\)[01]@/@\1@/g
s/@\(struct@[	 ]*@nnode\)[01]@/@\1@/g
s/@\(struct@[	 ]*@xnode\)[01]@/@\1@/g
s/@\(struct@[	 ]*@cnode\)[01]@/@\1@/g
s/@\(struct@[	 ]*@lnode\)[01]@/@\1@/g
s/@\(struct@[	 ]*@fnode\)[01]@/@\1@/g

s/@//g
s/ATSIGN/@/g