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jacobolus

> better notation for literals [...] something like 1eb-1 (for 0.5) and 1eb-2 (for 0.25)

There are floating point hex literals. These can be written as 0x1p-1 == 0.5 and 0x1p-2 == 0.25.

You can use them in C/C++, Java, Julia, Swift, ..., but they are not supported everywhere.

https://observablehq.com/@jrus/hexfloat

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C++ hex floats are an interesting combination of 3 numeric bases in one!

the mantissa is written in base 16

the exponent is written in base 10

the exponent itself is a power of 2 (not of 16 or 2), so that's base 2

One can only wonder how that came to be. I think they chose base 10 for the exponent to allow using the 'f' suffix to denote float (as opposed to double)

Julia is missing 32 bit and 16 bit hex floats unfortunately.

You can just wrap the literal in a conversion function, eg Float32(0x1p52), which should get constant propagated at compile time.

I know, it just isn't as nice to read.

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