Parser should accept parens when declaring rules

[dwhjames]

The parser only accepts

[
  [[rule ?e ?v]
    [?e :ns/attr ?v]]
]

but it should also accept

[
  [(rule ?e ?v)
    [?e :ns/attr ?v]]
]

[dwhjames]

Hmm, maybe I take this back… the parser accepts parens for rule invocation, but it looks like the convention of using parens is only at invokation and not at declaration.

[mandubian]

yes that's what I understand from my really poor knowledge of Clojure!

[dwhjames]

For rule invocations within rule declarations,

[
  [[rule ?a ?c]
    [?a :ns/attr ?b]
    (rule ?b c)]
]

is required.

Maybe there’s a easy change to the parser combinators to allow either parens or brackets for rules.

[mandubian]

I'll look at it!

On Fri, Feb 22, 2013 at 4:13 PM, Daniel James notifications@github.comwrote:

For rule invocations within rule declarations,

[
[[rule ?a ?c]
[?a :ns/attr ?b](rule ?b c)]]

is required.

Maybe there’s a easy change to the parser combinators to allow either
parens or brackets for rules.

—
Reply to this email directly or view it on GitHubhttps://github.com//issues/26#issuecomment-13947712.

[mandubian]

Daniel can you look at the test I added because it seems to work already...

[dwhjames]

You’ve tested rules of the sort:

[[[rule ?a ?c]
    [?a :ns/attr ?b]
    (rule ?b c)]]

but I don’t think it accepts

[[(rule ?a ?c)
    [?a :ns/attr ?b]
    (rule ?b c)]]

I can’t find anything concrete, but it seems most people write the former, but I don’t think the latter is wrong, and nor is:

[[[rule ?a ?c]
    [?a :ns/attr ?b]
    [rule ?b c]]]

So the first is accepted, are there tests for the second two?

[mandubian]

Ok I see now what you mean!
I'm going to correct this ;)