Displaying object variables, not obj ID

ruby-talk
1

I'm having problems with displaying an object correctly. I keep getting the
obj's ID back, like this:

sendto("Chromosomes: " + p.c_chromosomes.to_s) # sort of 'puts' =>
Chromosomes: #<Chromosome:0x10267658>

Checking with the Pickaxe, I see they have a solution (no obvious
explanation though), where they suggest redifining to_s to accomodate its
purpose in their 'song' class. This is no good for me though, as to_s will
be used to display a lot of things, not just chromosomes.

Uhm. I feel like I should provide more info to ensure an accurate answer,
but I'm not sure what or how much is necessary.
Perhaps that the variable actually saves right in the yaml file:

...
c_chromosomes: !ruby/object:Chromosome
    c_chromosomes: # hash of arrays
      symmetry: []
...

Any insights would be much appreciated.
Tobias

2

Tobias Jonch wrote:

Checking with the Pickaxe, I see they have a solution (no obvious
explanation though), where they suggest redifining to_s to accomodate
its purpose in their 'song' class. This is no good for me though, as to_s
will be used to display a lot of things, not just chromosomes.

Perhaps you are not aware that defining a to_s method in the Chromosome
class will only affect how Chromosomes are displayed, nothing else.

···

--
-- Jim Weirich

--
Posted via http://www.ruby-forum.com/\.

3

Astonishing as it may seem, I do know :wink:

I'm not calling to_s from the chromosome class, however, and that does
matter, right?

Thanks
Tobias

···

On 12/23/05, Jim Weirich <jim@weirichhouse.org> wrote:

Perhaps you are not aware that defining a to_s method in the Chromosome
class will only affect how Chromosomes are displayed, nothing else.

4

Tobias Jonch wrote:

Perhaps you are not aware that defining a to_s method in the Chromosome
class will only affect how Chromosomes are displayed, nothing else.

Astonishing as it may seem, I do know :wink:

I'm not calling to_s from the chromosome class, however, and that does
matter, right?

You are invoking the Chromosome version of to_s method on instances of Chromosome.

When you call to_s on an instance of a class, and you get back that ClassName:0xID thing, it means that that object does not have its own to_s method defined, so it defaults to calling Object's to_s (which of course as no idea how to stingify this particular class).

So you need to give Chromosome instances their own to_s.

James

···

On 12/23/05, Jim Weirich <jim@weirichhouse.org> wrote:

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5

So you need to give Chromosome instances their own to_s.

James

Aha. I guess it didn't matter after all.

Thanks James, for your lucid explanation.