self consume: yst

Main is_a PN

(x|t)

s syncpop: #wantedToken s

synchronous port return place

class name class ascendant initial marking

message pattern

x := self produce.

s push: x

y := s pop.

self consume: y st

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f := leftPh giveRFork leftPh

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left fork

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In document View of Software Engineering and Petri Nets (Sider 43-59)