Bugs in query language

[karimali03]

In the syntax query language guide it is written that

• 3 prev x — A wire with the value of x at time t-3 shifted to time t.
  but when I tried it it give me error and don't work and the same with next
  ex1: sootty example/example1.vcd -w "3 prev D0"
  ex2: sootty example/example1.vcd -w "3 next D0"
  it give me : AttributeError : 'Token' object has no attribute 'data'
• time 4 — A wire with value 0 from until time 3, and value 1 from time 4 and after.
• const 5 — A wire with a constant value of 5 at all points in time.
  but when try this it says that this wire does not exist