From 5f87d5d242b87ce5cfbd7ac5fcb1efcc62fc5582 Mon Sep 17 00:00:00 2001 From: "http://smcv.pseudorandom.co.uk/" Date: Sat, 3 Apr 2010 00:25:28 +0000 Subject: [PATCH] actually I can see a second use for "nonlinear" syntax - but I don't think it's worth it --- .../allow_plugins_to_add_sorting_methods.mdwn | 32 ++++++++++++------- 1 file changed, 20 insertions(+), 12 deletions(-) diff --git a/doc/todo/allow_plugins_to_add_sorting_methods.mdwn b/doc/todo/allow_plugins_to_add_sorting_methods.mdwn index 36c134a59..1657ca8e9 100644 --- a/doc/todo/allow_plugins_to_add_sorting_methods.mdwn +++ b/doc/todo/allow_plugins_to_add_sorting_methods.mdwn @@ -99,20 +99,28 @@ That earlier version of the branch is also available for comparison: >>>>> Perhaps. I do like the simplicity of [[KathrynAndersen]]'s syntax >>>>> from [[plugins/contrib/report]] (which I copied verbatim, except for ->>>>> turning sort-by-`field` into a parameterized spec), and I can't really ->>>>> think of any sensible way to combine sort specs other than "sort by a, ->>>>> break ties by b, ...", possibly with some reversals thrown in. +>>>>> turning sort-by-`field` into a parameterized spec). >>>>> ->>>>> If no other combinations do make sense, is your proposal that "then" ->>>>> is entirely redundant (easy, just make it a predefined sort spec that ->>>>> returns 0!), or that it's mandatory "punctuation" (add an explicit ->>>>> check, or make "then" expand to "||" and let Perl fail to compile ->>>>> the generated code if it's omitted)? +>>>>> If we're getting into English-like (or at least SQL-like) queries, +>>>>> it might make sense to change the signature of the hook function +>>>>> so it's a function to return a key, e.g. +>>>>> `sub key_age { return -%pagemtime{$_[0]) }`. Then we could sort like +>>>>> this: >>>>> ->>>>> It is a little unfortunate that reversal has to move into the sort ->>>>> spec - I prefer `reverse=yes` - but that's necessary for multi-level ->>>>> sorting. I can see your point about ascending/descending being more ->>>>> obvious to look at, but they're also considerably more verbose. +>>>>> field(artistsort) or field(artist) or constant(Various Artists) then meta(titlesort) or meta(title) or title +>>>>> +>>>>> with "or" binding more closely than "then". Does this seem valuable? +>>>>> I think the implementation would be somewhat more difficult. and +>>>>> it's probably getting too complicated to be worthwhile, though? +>>>>> (The keys that actually benefit from this could just +>>>>> have smarter cmp functions, I think.) +>>>>> +>>>>> If the hooks return keys rather than cmp results, then we could even +>>>>> have "lowercase" as an adjective used like "ascending"... maybe. +>>>>> However, there are two types of adjective here: "lowercase" +>>>>> really applies to the keys, whereas "ascending" applies to the "cmp" +>>>>> result. Again, I think this is getting too complex, and could just +>>>>> be solved with smarter cmp functions. >>>>> >>>>> Unfortunately, `sort="ascending mtime"` actually sorts by *descending* >>>>> timestamp (but`sort=age` is fine, because `age` could be defined as -- 2.45.0