On 21 Aug 2006 16:04:53 -0700, "Alex McDonald"
<alex_mcd@[EMAIL PROTECTED]
> wrote:
>> Agree with the above, and would add
>>
>> 5) Current implementations of { are diverging in the facilities they
>> provide.
It's the function of a standard to encourage people to use the
same names for the same function, but it is not the purpose to
stop new facilities being added to implementations.
>> 6) { and } are visually confusing. Perhaps select another character or
>> string, which would allow existing implementations to do their own
>> thing unmolested.
Common practice is to use { ... }. Is changing a name in common use
because we need new glasses or bigger monitors good enough reason
for change?
>7) LOCALS| has the following restrictions on the use of the rstack;
>
>13.3.3.2 Syntax restrictions
>c) Locals shall not be declared until values previously placed on the
>return stack within the definition have been removed;
Removing this restriction would break code. I will add it.
>d) After a definition's locals have been declared, a program may place
>data on the return stack. However, if this is done, locals shall not be
>accessed until those values have been removed from the return stack;
Do any current systems suffer if this restriction is removed?
Implementers please respond! Current MPE systems will not suffer
unless { ... } is used a second time - should this be an ambiguous
condition?
Similarly, many current systesms, including MPE's, will break
if { ... } is used inside a control structure, e.g.
: foo \ ...
... if
{ a b c -- }
...
else
...
then
;
I propose to add this as an amiguous condition as below.
Ambiguous conditions:
a) The { ... } text extends over more than one line.
b) The expression for local buffer size does not return a single
cell.
c) { ... } shall not be declared until values previously placed
on the return stack within the definition have been removed.
d) { ... } is declared within a control structure.
Stephen
--
Stephen Pelc, stephenXXX@[EMAIL PROTECTED]
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