Add string(float, base = 16), string(float, base = 2) for %a formatting of floats

[tgross35]

It is currently possible to print floats (including BigFloat) using @printf "%a" x, but this seems to be the only way. Would it be feasible to add a form of this that goes through print/string? For example:

> string(Float16(1.6875), hex = true)
0x1.bp+0

This makes it more consistent with other numeric formatting that can be set with string(x, base = 16) or similar.

[Seelengrab]

I'm not sure adding this is worth the complexity. There's a great package, About.jl, that supports these kinds of introspective queries very well.

[tgross35]

Thanks for pointing at About.jl, I did not know about that and it looks quite nice. Base two was mostly a "nice to have" suggestion, it still seems like there should be a print-based version of hex formatting in Base that does not require printf.

(updated the issue)

[tgross35]

Related note on bigfloat %a formatting #56941 (comment)