@startuml
scale 2

' anything after a quote is ignored (a comment).

/' anything between slash quote over several lines
potentially is also ignored '/

/' you can try to uncomment the following line to
see what happens'/

' left to right direction

object "Satiton : Melun" as mln
object "Satiton : Gare de Lyon" as gdl
object "Satiton : Maison-Alfort" as ma
object "Satiton : Vert-de-Maison" as vdm

object "Liaison 1" as l1
object "Liaison 2" as l2
object "Liaison 3" as l3

object "Ligne R" as lr
object "Ligne RER D" as rerd

object "PS : lR" as pslr
object "PS : RER D" as psrer

object "Parcours complexe: Parcours" as pc

mln<-- "debut" l1
gdl<-- "fin" l1
gdl<-- "debut" l2
ma<-- "fin" l2
ma<-- "debut" l3
vdm<-- "fin" l3

mln<-- "debut" pslr
gdl<-- "fin" pslr
gdl<-- "debut" psrer
ma<-- "fin" psrer
mln<-- "debut" pc
vdm<-- "fin" pc

l1--o lr
l1--o pslr
l2--o rerd
l2--o psrer
l3--o rerd
l3--o psrer

l1--> lr
l2--> rerd
l3--> rerd

pslr--> lr
psrer--> rerd
pc o--pslr
pc o--psrer


' describe the arrows




@enduml