On 07/06/2020 19:37, Theodore Brown wrote:
If `<<Foo( <<Bar>> )>>` means something like `new Foo( new Bar )`, then I
can imagine it being useful for `<<Foo( <<Bar, Baz>> )>>` to mean
`new Foo( [new Bar, new Baz] )`. That would actually be more convenient than
the double-at version, where you'd have to write `@@Foo( [@@Bar, @@Baz] )`
or use a constructor with a `...$variadic` parameter.
In that example there are the same number of characters either way, so
it's not clear the nested `<<>>` approach would be more convenient.
And do you think it's a good idea to have an additional syntax for
creating arrays like that? It seems like it could get confusing.
True, it doesn't make a huge amount of difference.
My thinking was that passing a list of attributes as arguments to
another would be quite a common case, and would add value to the special
"nested attributes" syntax, which is otherwise just a weird spelling of
"new" to work around implementation problems (if indeed it does actually
work around them).
Ultimately, it all comes down to judgement calls - is the
double-angle-bracket syntax "too verbose", "too ugly" when nested, etc;
and does the double-at syntax make it "better enough".
Yes, I agree that there's a judgment call to make. Out of curiosity,
given these shortcomings of the double-angle-bracket syntax, do you
think there are any objective reasons to prefer it over `@@` (other
than the theoretical BC break of code like `@@@really_suppress_me()`)?
I'm not convinced there's any objective reasons to be found either way,
but for the sake of "playing devil's advocate", here are a few that
could be put forward:
If grouped attributes are added, they're actually slightly less verbose
than repeating a double-at prefix, once you have enough attributes in
the set:
Minimum spacing and punctuation requires n+3 chars vs 3n, so a saving
even with 2 attributes:
<<Foo,Bar>>class Bob{}
vs
@@Foo @@Bar class Bob{}
More realistic spacing is 2n+3 vs 3n, giving a saving only with 4 or more:
<<Foo, Bar, Baz, Quux>>class Bob{}
vs
@@Foo @@Bar @@Baz @@Quuxclass Bob{}
Bracket-based syntaxes, particularly with grouping, are more clearly
separated from the main code, particularly when used inline. For instance:
$f = @@Something @@AnotherThing function(@@Special @@ReallyInt int $var) {};
vs
$f = <<Something, AnotherThing>> function(<<Special, ReallyInt>> int
$var) {};
Finally, typing up those examples, it occurs to me that @@ is quite a
"heavy" symbol - it has a large proportion of black (or whatever colour)
pixels - and inevitably a rather "fussy" one. I find it draws the eye
more than the angle-brackets do, which feels unfortunate.
Regards,
--
Rowan Tommins (né Collins)
[IMSoP]
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