I only have a main function. The -1 and -2 suffixes are just to explain the problem here. I'll check tomorrow using pointers instead of references, since I'm at home now and don't have the source here. I'd like to understand the problem though, since it may come up later in similar form.
On Monday, August 19, 2013 7:30:06 PM UTC+2, Ilia Mirkin wrote: > > Clearly you're doing _something_ wrong... but what? There's more > surrounding code (if nothing else, you can't have a function called > "main-1"), and I suspect that code might be the issue. For example, > one place I've gotten caught before is if you have > > foo &a = ...; > foo &b = ...; > a = b; > > That copies b into a, rather than assigning a to a reference to b. > > What happens if you change your function to take a pointer rather than > a reference? > > -ilia > > > On Mon, Aug 19, 2013 at 1:25 PM, Alvaro Aguilera > <[email protected] <javascript:>> wrote: > > The problem is that if I use main-1 the string value is lost when > leaving > > the scope of the attribute_value() function. > > Am I doing something wrong? > > > > > > > > > > On Monday, August 19, 2013 7:17:56 PM UTC+2, Ilia Mirkin wrote: > >> > >> Perhaps I'm dense, but what's the problem? That gdb doesn't print the > >> exact type info that you expected? That could well be the difference > >> between -O2 and -O0... > >> > >> On Mon, Aug 19, 2013 at 9:55 AM, Alvaro Aguilera > >> <[email protected]> wrote: > >> > Hello, > >> > > >> > I'm having a strange problem when setting an string value in a > protocol > >> > buffer. Keep in mind that my experience in C++ and PB is rather > limited. > >> > The .proto file looks more or less like this: > >> > > >> > ---------------------- > >> > package buffers; > >> > > >> > message AttributeValue { > >> > > >> > enum Type { > >> > INT64 = 0; > >> > UINT64 = 1; > >> > INT32 = 2; > >> > UINT32 = 3; > >> > FLOAT = 4; > >> > DOUBLE = 5; > >> > INVALID = 6; > >> > STRING = 7; > >> > } > >> > > >> > required Type type = 1; > >> > optional int32 i32 = 2; > >> > optional int64 i64 = 3; > >> > optional uint32 ui32 = 4; > >> > optional uint64 ui64 = 5; > >> > optional float f = 6; > >> > optional double d = 7; > >> > optional string str = 8; > >> > > >> > } > >> > > >> > ---------------------- > >> > > >> > I also have a function to convert a class "VariableDatatype" into an > >> > AttributeValue buffer. It looks like this: > >> > > >> > void BufferConverter::attribute_value(const VariableDatatype &s_atv, > >> > buffers::AttributeValue &b_atv) > >> > { > >> > switch(s_atv.type()) { > >> > case VariableDatatype::Type::STRING: > >> > b_atv.set_type(buffers::AttributeValue::STRING); > >> > b_atv.set_str(s_atv.str()); > >> > break; > >> > } > >> > } > >> > > >> > > >> > In the main function I try to create a protocol buffer containing the > >> > string > >> > stored in VariableDatatype by using the attribute_value() function in > >> > the > >> > way shown below: > >> > > >> > main-1() > >> > { > >> > buffers::AttributeValue *bs = new buffers::AttributeValue(); > >> > c.attribute_value(ds, *bs); > >> > > >> > } > >> > > >> > This doesn't work. > >> > If I print the value of b_atv inside the attribute_value function > using > >> > gdb > >> > I get something like: > >> > > >> > gdb print b_atv > >> > 26 = (buffers::AttributeValue &) @0x6496b0: > {<google::protobuf::Message> > >> > = > >> > {<google::protobuf::MessageLite> = { > >> > > >> > > >> > However, when I print *bs from inside main-1, I get something > different: > >> > > >> > gdb print *bs > >> > $36 = {<google::protobuf::Message> = {<google::protobuf::MessageLite> > = > >> > {_vptr.MessageLite = 0x642650 <vtable for buffers::AttributeValue+16> > >> > > >> > I can work around the problem by using the following main-2: > >> > > >> > main-2() > >> > { > >> > buffers::AttributeValue *bs = new buffers::AttributeValue(); > >> > buffers::AttributeValue &bss = *bs; > >> > > >> > c.attribute_value(ds, bss); > >> > } > >> > > >> > but that's not very elegant. Can someone point me to the right way to > >> > handle > >> > this? > >> > > >> > Thank you > >> > A. > >> > > >> > > >> > > >> > > >> > > >> > -- > >> > You received this message because you are subscribed to the Google > >> > Groups > >> > "Protocol Buffers" group. > >> > To unsubscribe from this group and stop receiving emails from it, > send > >> > an > >> > email to [email protected]. > >> > To post to this group, send email to [email protected]. > >> > Visit this group at http://groups.google.com/group/protobuf. > >> > For more options, visit https://groups.google.com/groups/opt_out. > -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/protobuf. For more options, visit https://groups.google.com/groups/opt_out.
