digraph untitled        {
type -> "1lt"
type -> "2lt"
type -> "2ltpf"
type -> "2ltpartialpf"
xpath -> "2ltxpathpartialpf"
"2ltpartialpf" -> "2ltxpathpartialpf"
type -> xml
type -> xpath
type -> sql
type -> lenses

"2lt" -> xmlsql
sql -> xmlsql
xml -> xmlsql

"1lt"   -> xpto
xml   -> xpto
xpath -> xpto
}