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From: Pedro Alves <pedro@codesourcery.com>
To: gdb@sourceware.org
Subject: Re: Python API - nested pretty printers MI implications
Date: Mon, 15 Aug 2011 12:58:00 -0000
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Cc: Andrew Oakley <andrew@ado.is-a-geek.net>
References: <20110814171023.19db4f49@ado-gentoo>
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On Sunday 14 August 2011 17:10:23, Andrew Oakley wrote:
>         def children(self):
>                 yield ("normal variable", "some value")
>                 yield ("phony group 1", inner_pretty_printer(...))
>                 yield ("phony group 2", inner_pretty_printer(...))
> 
> This seems to work well but I'm not quite sure how to handle the for MI.
> 
> As far as I can tell I need to create "fake" varobj structures with no
> underlying value or type (because I don't have one). 

I'm not very familiar with the pretty printing stuff, but,
doesn't something like this work nowadays?

class phony_value:
       ...
       /* extend Value */

class phony_value_pretty_printer:
        def __init__(self, ...):
                ...

def new_phony(outer, whatnot):
       /* return new phony value for outer */
       ...

class outer_pretty_printer:
        def __init__(self, val):
                ...

        def to_string(self):
                ...

        def children(self):
                yield ("normal variable", "some value")
                yield ("phony group 1", new_phony(1))
                yield ("phony group 2", new_phony(2))


That is, create a specialized Value class and install the pretty
printer for that _value_.

-- 
Pedro Alves