Let ,
be distinct variables. Abbreviate
importtoimport
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endimport endimport
import,
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endimport
In a similar way, define abbreviations
import, ...,
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endimport
Abbreviate
importto, ...,
U(
) := true . . . U(
) := true
endimport
extend U with, ...,
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endextend
Later (in 5.4) we'll see how to import a number of elements that is not bounded a priori by any constant. Here is an example of the extend rule:
extend Nodes with,
FirstChild(CurrentNode) :=
SecondChild(CurrentNode) :=
NextSib(
) :=
endextend