On 25 oct. 2013, at 13:34, Norbert Hartl <norbert@hartl.name> wrote:

I’m thinking about what would be the proper/least annoying way of having multiple exception sections. If I have a code block that can emit two different exceptions is the only way doing it

[ [ ... ] on: Exception1 do: [ … ] ] on: Exception2 do: [ … ]

You can handle multiple exceptions like that: [ ... ] on: Exception1, Exception2 do: [ :err | ... ] But there is only one handling block. If you need to have two different handling blocks, I once though of a solution where you would write things like that: [ ... ] exceptionHandler on: Exception1 do: [ ... ]; on: Exception2 do: [ ... ]; execute. The #exceptionHandler message would answer an ExceptionHandler on the block that would be able to manage multiple handling blocks. Something like that: ExceptionHandler >> on: anExceptionClass do: aBlock handlingBlock at: anExceptionClass put: aBlock ExceptionHandler>> handlingBlockFor: anExceptionClass anExceptionClass ifNil: [ ^ nil ]. ^ handlingBlock at: anExceptionClass ifAbsent: [ self handlingBlockFor: anExceptionClass superclass ] ExceptionHandler >>#execute block on: Error do: [ :error | (self handlingBlockFor: error class) ifNil: [ error pass ] ifNotNil: [ :handlingBlock | handlingBlock value ] ]

on:do: just calls a primitive that marks the context being an exception handler. What is called in the image when the stack is scanned to find an exception handler?

I think its ContextPart>>#findNextHandlerContextStarting

thanks,

Norbert