buf containing pa: li0e2:Tyi0ee
li13e2:Tcd3:tag1:B2:tyi0e1:v4:Boolee
li50e2:Tcd3:tag5:c.str2:tyi13e1:v1:aee
li89e2:Tpl0:i13ei13eee
li112e2:Tcd3:tag5:c.str2:tyi89e1:v1:pee
li152e2:T@li112ei50eee
li175e2:Tcd3:tag5:c.str2:tyi13e1:v1:bee
li215e2:Tcd3:tag5:c.str2:tyi89e1:v1:qee
li255e2:T@li215ei175eee

(len 279)
read pa: (p a)
read qb: (q b)