>| From: [EMAIL PROTECTED]
>|
>| I'm puzzled by a detail in the Report, which seems to contradict itself.
>|
>| On page 13 it says:
>|
>| The special form -e denotes prefix negation, [...] and is simply
>| syntax for negate (e), where negate is as defined in the standard
>| prelude.
>|
>| The standard prelude defines negate as a function, which by default has
>| precedence 10. But the context free syntax on page 134 says:
>|
>| <lexp6> ::= - <exp7>
>|
>| which gives prefix - precedence 6.
>
>Hi, Norman.
>
>It says, "is simply syntax for negate (e)", not "is syntactically
>equivalent to negate (e)". In other words, prefix minus is a special
>syntactic form, with syntactic precedence 6, as given by the context-
>free syntax. Semantically, the form denotes an application of the
>standard function negate. OK?
>
This is one of these 'trivial' points that I, for one, still think needs
clearing up by a slight modification to the wording. I'm not sure what the
difference between "is simply syntax for" and "is syntactically equivalent"
is. Since Joe rightly says this is a SEMANTIC point, why not say "has the
same meaning as negate (e)" [Presumably the brackets round the "e" were put
there because it was realised that "-" did NOT have the same precedence as
functional application.]
Tony Davie Department of Mathematical and Computational Sciences
Tel: +44 334 63257 St.Andrews University
Fax: +44 334 63278 North Haugh
[EMAIL PROTECTED] St.Andrews
Scotland
KY16 9SS
Q. What does a mathematician do before he drinks tea?
A. He drinks t - 1.
