The Cauchy problem for nonlinear first order partial differential-functiona
l equations in unbounded domains is treated with a general class of the met
hod of lines. Existence and convergence properties of the method are invest
igated under the assumption that the right-hand side of the equation satisf
ies the Lipschitz condition with respect to the functional argument. The th
eorems are proved by means of the differential-difference inequalities tech
nique. Examples of differential-functional problems and corresponding metho
ds of lines are given.