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Re: [Scheme-reports] <transformer spec> BNF

Alex Shinn <alexshinn@x> writes:

> Hi Taylan,
> "It is an error if <syntax rule> is not of the form (<pattern> <template>).
> The <pattern> in a <syntax rule> is a list <pattern> whose first element
> is an identifier."
> Thus "it is an error,"  and implementations are free to do
> whatever they want, though most will either ignore it or
> signal an syntax error.

Thanks for the explanation.

> "List pattern" is simply a pattern which is a list, as
> described further on in the section.  I don't think this
> is confusing, but we're open to alternate suggestions.

Perhaps "a <pattern> that is a list" in place of "a list <pattern>",
since the latter reads like "a list that we will call <pattern>."  (I
had at least one native English speaker share this confusion.)

Also, in section 6.4 (Pairs and lists), it is stated that "an improper
list is not a list." However, the <pattern> in a <syntax rule> can be an
improper list as well, can it not?  Then we would end up with "The
<pattern> in a <syntax rule> is a <pattern> that is a list or improper
list whose first element is an identifier," perhaps replacing the second
occurrence of <pattern> with a pronoun: "The <pattern> in a <syntax
rule> is one that is a list or improper list whose first element is an
identifier."  A bit long-winded but more accurate if I'm not mistaken.

I hope I'm not being too pedantic. :)


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