60 lines
1.3 KiB
Plaintext
60 lines
1.3 KiB
Plaintext
### Continuing
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[
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Datatype continuing
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Funcon continued
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Funcon finalise-continuing
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Funcon continue
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Funcon handle-continue
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]
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Meta-variables
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T <: values
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Datatype
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continuing ::= continued
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/*
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`continued` is a reason for abrupt termination.
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*/
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Funcon
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finalise-continuing(X:=>T) : =>T|null-type
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~> finalise-abrupting(X)
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/*
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`finalise-continuing(X)` handles abrupt termination of `X` due to executing
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`continue`.
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*/
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Funcon
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continue : =>empty-type
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~> abrupt(continued)
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/*
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`continue` abruptly terminates all enclosing computations until it is handled.
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*/
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Funcon
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handle-continue(_:=>null-type) : =>null-type
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/*
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`handle-continue(X)` terminates normally when `X` terminates abruptly for the
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reason `continued`.
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*/
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Rule
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X --abrupted( )-> X'
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------------------------------------------------------
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handle-continue(X) --abrupted( )-> handle-continue(X')
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Rule
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X --abrupted(continued)-> _
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--------------------------------------------
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handle-continue(X) --abrupted( )-> null-value
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Rule
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X --abrupted(V:~continuing)-> X'
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------------------------------------------------------
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handle-continue(X) --abrupted(V)-> handle-continue(X')
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Rule
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handle-continue(null-value) ~> null-value
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