Plot Many Data to same plot

Dear all,
I have a function that for a variable number of inputs plots them to the same plot
I am doing this quite simply by

plot(seq(from=start, to=stop, length.out=np), datalist[[1]]$dataset
???????????????? xlim=c(start, stop), ylim=c(0, 1), type="l")

??????? if (length(datalist) > 1) {
??????????????? for (i in 2:length(datalist)) {
??????????????????????? np <- length(datalist[[i]]$dataset)
??????????????????????? lines(seq(from=start, to=stop, length.out=np), datalist[[i]]$dataset$, lty=i)
??????????????? }
??????? }

as you can see, specifically this line

???? lines(seq(from=start, to=stop, length.out=np), datalist[[i]]$dataset$ lty=i)

is changing the line type so any different input is plotted with different line type.

This works quite well for 6 lines but if the arguments are more than 6 (in my case 7) the line type starts from the beginning. Is it possible to keep that loop and have the lines produced in plots a bit more customized (like lines with squares and or cubes).

I have already checked in the ?par
but I can not find how I can modify the line in that sense, and especially doing this smart inside a for loop.


Could you please help me with that?
I would like to thank you in advance for your help

Regards
Alex

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