I'm playing around with std.format and I'm trying to figure out if there is any way to identify what "%s" should expand to.

So for instance:
int x = 1;
auto result = x.format!"%s";

I would know that result="1". I could run "1" through unformatValue and get back 1. I'm looking to see if there is a way to get back "%d": really a function would be like f(x, "%s") produces "%d".

Is there anything like that in std.format?

On 8/20/17 9:52 PM, jmh530 wrote:
> I'm playing around with std.format and I'm trying to figure out if there is any way to identify what "%s" should expand to.
> 
> So for instance:
> int x = 1;
> auto result = x.format!"%s";
> 
> I would know that result="1". I could run "1" through unformatValue and get back 1. I'm looking to see if there is a way to get back "%d": really a function would be like f(x, "%s") produces "%d".
> 
> Is there anything like that in std.format?

Well, for most things, %s does not do the same thing as another specifier. It's only integers, which format the same as %d, and floating points, which format the same as %g.

For all others, the format is specified as %s.

I think what you really want is just isFloatingPoint or isIntegral.

-Steve

On Monday, 21 August 2017 at 13:57:01 UTC, Steven Schveighoffer wrote:
>
> Well, for most things, %s does not do the same thing as another specifier. It's only integers, which format the same as %d, and floating points, which format the same as %g.
>
> For all others, the format is specified as %s.
>
> I think what you really want is just isFloatingPoint or isIntegral.
>
> -Steve

I'm pretty sure that isFloatingPoint/isIntegral is not what I need, but I'm also not sure if what I was asking for above is needed either. So I'll just drop it for now.

On 8/21/17 10:58 AM, jmh530 wrote:
> On Monday, 21 August 2017 at 13:57:01 UTC, Steven Schveighoffer wrote:
>>
>> Well, for most things, %s does not do the same thing as another specifier. It's only integers, which format the same as %d, and floating points, which format the same as %g.
>>
>> For all others, the format is specified as %s.
>>
>> I think what you really want is just isFloatingPoint or isIntegral.
> 
> I'm pretty sure that isFloatingPoint/isIntegral is not what I need, but I'm also not sure if what I was asking for above is needed either. So I'll just drop it for now.

What I mean is that %s goes to %d for isIntegral!(typeof(x)), and %s goes to %g for isFloatingPoint!(typeof(x)), and stays as %s for everything else.

Given this, you could probably write the function you were looking for.

-Steve

On Monday, 21 August 2017 at 15:39:04 UTC, Steven Schveighoffer wrote:
>
> What I mean is that %s goes to %d for isIntegral!(typeof(x)), and %s goes to %g for isFloatingPoint!(typeof(x)), and stays as %s for everything else.
>
> Given this, you could probably write the function you were looking for.
>
> -Steve

I realized I was more interested in the length of the result than the type.