Syntactic sugar poll

Erik.Johansson <>
Mon Jan 14 11:34:12 CET 2002


----- Original Message ----- 
From: "Maurice Castro" <>
> 
> Vote NO! to adding 0x for hexadecimal constants.
> 
> The case for leaving the language alone.
> 
> In general I am against adding syntactic sugar to a language, 

Why?

> in this case in particular I suspect that we might be on a slippery slope.

Erlang has always been on a slippery slope. ;)
But the reason Erlang is so useful is that the development has been pragmatic, 
only if a feature is nice and useful it is added. (Such nice features as records and 
higher order functions have been added first as preprocessed syntactic sugar
then later as "real" parts of the language.)  This approach has lead to some strange
quirks, and some zealous people shun the language because it is "warty and ugly",
but on the other hand this approach has lead to a very useful language. 

> 
> Erlang has a well worked out consistent mechanism for handling
> constants with many bases. There is no need to extend the language to
> satisfy these programmers as they are free to pre-process their files
> to use their prefered convention. (eg. sed 's/0x/16#/g' file in this
> case)

You know this is not true. Your sed approach would change my strings and 
atoms too. Also, I would have no guarantee that my private notation would 
be consistent with future versions of Erlang.

How often do you write Erlang constants in another base than 2, 10 or 16?
Base 10 is probably most common and has its own syntax (no 10# prefix 
needed), base 16 is probaly the second most used base closely followed by
base 2, why not give one or both of these a special syntax?

> Furthermore, the case made for changing the language to include the
> 0x construct has the following additional problems:
> 
> 1) We are giving a favored place to a particular assembler's convention.
> Assembler codes are far from standardised. Although GNU as borrowed C's
> convention other assemblers use other conventions.  For example the
> very popular tasm used a number followed by an `h' is a heaxadecimal
> constant, `b' for binary, `o' for octal, `d' for decimal, or nothing
> use the radix defined in the code.

Yes, but I belive the 0x notaion is the one most used today (in general not only
in assemblers).  I am sure there are other (Pascal, Prolog, etc) programmers 
who would like another syntax, but I am also sure that they still would recognize 
0xN as a hexadecimal number.

(I am an old tasm hacker myself but I have not used tasm for 10 years, and I do 
not miss the base suffix asl long as I can have a base prefix.)

> 
> 2) A better argument might be to adopt the C convention, however, if we
> are going to extend the language to embrace C's way of denoting a
> hexadecimal number we had best take the octal notation too ie 0x for
> hexadecimal 0 for octal. The octal extension may well break existing
> code.

Yes, but lets be pragmatic, who needs an octal number today? ;)
(Hex on the other hand is a convenient way of writing numbers reprecented 
by bytes.)

> 
> 3) Although embracing the 0x convention in the current popular compiler
> is simple, it may not be easy to implement it in other compilers
> (fortunately for me, ec -- my pet project -- would also be simple to
> modify to support the 0x convention)

Since the compiler have to handle 16# anyway, I don't see how 0x would
make things more complicated.


> Please vote NO and save Erlang from the 0x convention.

Please vote YES and give Erlang the freedom 0x convention.

> 
> Written and presented by Maurice Castro for the NO case.

/Erik
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