Re: Grammars for future languages

"Roy Ward" <RWARD@math.otago.ac.nz> writes:
...
>what I have done with ReWrite to maintain _some_ consistency of notation,
>is that I have defined operation such as plus, not, etc. and effectively
>defined the infix forms as being equivalent to the prefix ones, so


>a+b is _exactly_ equivalent to plus[a,b]
>!a is _exactly_ equivalent to not[a],


>so I can deal with these functions in the same way as any others.


>(The reason that I have used words rather than symbols for prefix operators
>is that I have chosen that 'names' must be (alpha)(alpha|digit)+ and it is
>good to be able to 'get at' these functions)


>Admittedly, I haven't implemented full objects yet (still trying to decide
>what I want) so I don't know how tough this will be.


Sather, a fully object-oriented language (freely available from
icsi.berkeley.edu), uses this same notion and calls it "syntax
sugar". It's adopted rather extensively in the language; for
example, a[b]=c in Sather is defined to be syntax sugar for the
expression a.aset(b,c) (call of method aset on object a with
parameters b and c), a=b is sugar for a(b) (call of method a
on object self with parameter b), etc etc.


I'm curious -- is this notion of non-alphanumeric notation
as systematic syntactic sugar for well-defined alphanumeric
notation an independent inversion of you and Ousterhout
(the Father of Sather:-), derived from a common, older
source, or what...? Other languages using it...?




Alex
--
Email: martelli@cadlab.it Phone: +39 (51) 597313
CAD.LAB s.p.a., v. Ronzani 7/29, Casalecchio, Italia Fax: +39 (51) 597120
[Ned Irons' IMP72 did something like that over 20 years ago. It used an
Earley parser so you could use any awful ambiguous syntax you wanted,
and most people did. -John]


--

Return to the comp.compilers page.
Search the comp.compilers archives again.