DtaWin server exceptions
Posted: Wed Aug 28, 2019 11:56 am
Wolfgang
is translated to 2 try blocks
The outer block is a
inside the catch we check to see if the exception ex was a 'WrappedException' which happens when you call BREAK in your code with a value.
If it is a normal Exception (from the framework) then we create a new WrappedException.
We then extract the value from this WrappedException and assign it to the variable in the RECOVER statement
the try block in this try catch contains the inner try statement
The inner try statement is a Try .. FInally where we call in the try and in the finally.
The rest of this try block is the original code inside the BEGIN SEQUENCE
These 2 helper methods are called so the runtime function _CanBreak() knows that we are in a BEGIN SEQUENCE.. END. Inside the compilerServices class we keep track of the "BreakLevel" for the current thread.
The BREAK <value> statement is translated to a call to
We have used similar names as in Vulcan. Why invent the wheel again ?
Robert
We use a similar approach as Vulcan:What I'm interested in: how the code recover block in the begin/end sequence block is translated by the compiler.
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BEGIN SEQUENCE ... RECOVER [USING varname]... END SEQUENCEThe outer block is a
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try .. catchinside the catch we check to see if the exception ex was a 'WrappedException' which happens when you call BREAK in your code with a value.
If it is a normal Exception (from the framework) then we create a new WrappedException.
We then extract the value from this WrappedException and assign it to the variable in the RECOVER statement
the try block in this try catch contains the inner try statement
The inner try statement is a Try .. FInally where we call
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CompilerServices.EnterBeginSequence()Code: Select all
CompilerServices.ExitBeginSequence()The rest of this try block is the original code inside the BEGIN SEQUENCE
These 2 helper methods are called so the runtime function _CanBreak() knows that we are in a BEGIN SEQUENCE.. END. Inside the compilerServices class we keep track of the "BreakLevel" for the current thread.
The BREAK <value> statement is translated to a call to
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throw WrappedException{<value>}Robert