[r6rs-discuss] overcomplicated numeric syntax.

[John Cowan]

Ray Dillinger scripsit:

> All numbers in base 10.  Decimals and scientific notation 
> allowed, other extensions not allowed. 
> 
> Inexact if there is a decimal in the number or the number 
> is expressed in scientific notation; otherwise exact. 

I have no trouble with these.

> new library procedure: radix - takes a string and a radix, 
> returns a number which is the interpretation of the string 
> as a number given that radix.  

string->number already does this, if given two arguments.

> new library procedure: inf, which takes a symbol '+ or '- 
> and returns an infinity having the matching sign. 

That's fine, but you end up with two numbers with no
external representation.  If you type "(inf '+)" to the
REPL, what should it print?

> new library procedure: NaN, which takes no arguments and returns 
> the value #nan.0 . I do not see incremental value in having a 
> direct write syntax for this value, because I can think of very 
> few situations in which it would appear in useful source code.  

It's not about it appearing in source code, it's about it appearing
in results.

> And if you need it in source code, you can write "(NaN)" with 
> fewer characters than "+nan.0" anyway.  "(NaN)" might also be used 
> as a printing syntax/external representation if that doesn't 
> muddy things too much.

That won't work.  "(NaN)" is not the external representation of
the number NaN, but of a list with a single element.

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