Re: [PATCH] float format specifier in ob-C.el

[Ihor Radchenko <yantar92@posteo.net>]

Leo Butler <Leo.Butler@umanitoba.ca> writes:

> In ob-C.el, line 339 has the format specifier
>
> 	    (`floatp '("double" "%f"))
>
> to print literal floats. However, that format specifier rounds, which
> can result in errors. I think the correct approach is to print the
> float without rounding or padding or trying to guess at the desired
> accuracy (and let the compiler do whatever is needed):
>
>            (`floatp '("double" "%s"))

Makes sense. Thanks!

> -	    (`floatp '("double" "%f"))
> +	    (`floatp '("double" "%s"))

Please add comment explaining why not %f. Otherwise, it is not fully
clear why "%s" is used.

> --- a/testing/examples/ob-C-test.org
> +++ b/testing/examples/ob-C-test.org
> @@ -60,6 +60,12 @@
>    return 0;
>  #+end_src
>  
> +#+source: float_var
> +#+begin_src cpp :var x=1.123456789012345678 :includes "<iostream>" :results silent
> +double y = 1.123456789012345678;
> +std::cout << (x == y);
> +#+end_src

Please move the source block directly into the test using
`org-test-with-temp-text'. The test will be more readable then.

`org-test-at-id' should better be used only when necessary in order to
not jump back and forth when debugging tests.

-- 
Ihor Radchenko // yantar92,
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