[m-dev.] for review: improve higher-order syntax

[Fergus Henderson]

On 16-Feb-2000, Peter Ross <petdr at cs.mu.OZ.AU> wrote:
> Just one question, should the following code parse
> 
>     { Result2 = 5 `(func(X, Y) = X + Y)` 6 },

According to the language reference manual as it current
stands now, no; in a `backquote` infix operator, the operator
between the backquotes must be either a name or a variable.

As a matter of language design?  Well, that is a more
difficult question... but my first impression is that
I'm satisfied with the current rules for backquoted
infix operators.  I don't think the code above is
very readable, and I can't really imagine any good
use of backquoted expressions.  Besides, if you allow
that, then you start getting into nasty issues of
nesting and precedence: do backquotes nest?

      { Result2 = 5 `(func(X, Y) = X `plus` Y)`	% allowed?
      { Result2 = 5 `func(X, Y) = X `plus` Y`	% allowed?
						% if so, how does it get
						% parenthesized?

-- 
Fergus Henderson <fjh at cs.mu.oz.au>  |  "I have always known that the pursuit
WWW: <http://www.cs.mu.oz.au/~fjh>  |  of excellence is a lethal habit"
PGP: finger fjh at 128.250.37.3        |     -- the last words of T. S. Garp.
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