Re: Unsecure assoc calls

[Michael Käppler]

> You need to amend the definition of the method in lily-guile.hh, since
> it's also used directly in the C++ code, with no optional arguments:
>
> 53 SCM ly_assoc_get (SCM key, SCM alist, SCM def);
>   
Hmm... I don't exactly understand the LY_DEFINE macro. Is it possible to 
implement this
with overloading or have all C++ calls of ly_assoc_get to be changed to 
use all four parameters?
> +    programming_error ("Cannot find key ~S in alist, setting to ~S.",
> ly_scm2string (key), ly_scm2string (default_value));
>
> I think what Carl is getting at here is that you can't pass these
> string values using format with programming_error () without adding
> the macro `(_f', but this shouldn't be used in this case since it
> internationalizes the message.
>   
programming_error (to_string ("Cannot find key %s in achain, setting to 
%s.",
                               ly_scm2string (key), ly_scm2string 
(default_value)));

Is this basically the right way to do this?

> There's a bigger problem here though, since it's not clear what the
> value of the key is going to be before converting it: ly_scm2string
> will only work if the scheme value is a string.  This naturally
> applies to default_value too, which could conceivably be any scheme
> object.
>   
What about adding a type check to ly_scm2string and add the possibility 
to convert from symbols and numbers too?
Isn't there a guile built-in method for converting any scheme object in 
a readable string?

Regards,
Michael