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Postings from September 2008
HaloO, Moritz Lenz wrote: > TSa wrote: >> The 'is rw' is on the method but I guess it is foreseen that the >> result is stored in $string without preserving the identity of the >> string? > > No. It means that the Str object has to get hold of the container in > which it is stored, and store a modified copy in it. If that fails (for > example in "abc".substr(0, 1) = "foo", where "abc" isn't in a container > at all) the write operation will fail. Sorry, I don't understand why you say 'no' and then explain that the resulting new string is stored in the container. The only container that could be affected by this is $string in the example. The way for a method to get access to the container is by declaring a parameter as rw. Note that this brings the discussion back to the point how rw is handled in dispatch and if an anonymous container is autovivified for a naked value. Did you mean the 'no' as answer to the question if the identity of the string--i.e. its pointer--is preserved? This would violate the immutability assertion of string values. Is it generally foreseen that an object knows about the containers it is stored in? Furthermore is it informed which of these is currently used as lvalue in a mutating operation? I think both are expensive and much better handled through the rw declaration of parameters because at binding time the container is available. Regards, TSa. -- "The unavoidable price of reliability is simplicity" -- C.A.R. Hoare "Simplicity does not precede complexity, but follows it." -- A.J. Perlis 1 + 2 + 3 + 4 + ... = -1/12 -- Srinivasa RamanujanThread Previous | Thread Next