init commit again

IBAF-cbs/Funcons-beta/Computations/Abnormal/Continuing/Continuing.cbs

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