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[MATCH-103] Support for lists in patterns. Created: 18/Dec/14  Updated: 18/Dec/14

Status: Open
Project: core.match
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Jan-Paul Bultmann Assignee: David Nolen
Resolution: Unresolved Votes: 0
Labels: None


 Description   

Currently it is not possible to use list literals with or without variables in a pattern.
Thus something like this

(match ['(1 2 3)]
       ['(a b c)] a)

will result in a failing assert.

AssertionError Invalid list syntax (a b c) in (quote (a b c)).

There is a workaround for this by using `:seq` and `:guard`, as in

(match ['(1 2 3)]
       [(([a b c] :seq) :guard list?)] a)

but it is rather tedious to write.

List matching would be very useful when writing macros and compilers.






[MATCH-72] complexity analysis Created: 18/Jun/13  Updated: 18/Jun/13

Status: Open
Project: core.match
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: David Nolen Assignee: David Nolen
Resolution: Unresolved Votes: 0
Labels: None


 Description   

For smaller matches avoid backtracking actually greatly improves performance at the potential cost of code size. Perhaps we can devise a heuristic such that we employ the the best option available? Would need some serious hammock time.






[MATCH-64] Improve match compile times Created: 15/Aug/12  Updated: 15/Jun/13

Status: Open
Project: core.match
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: David Nolen Assignee: David Nolen
Resolution: Unresolved Votes: 0
Labels: None





[MATCH-8] Implement (p|q)ba heuristics Created: 04/Sep/11  Updated: 04/Sep/11

Status: Open
Project: core.match
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: David Nolen Assignee: David Nolen
Resolution: Unresolved Votes: 0
Labels: None


 Description   

We should implement the rest of Maranget's suggested heuristics.

p - needed prefix
q - constructor prefix
b - branching factor
a - constructor arity






[MATCH-2] Matching Diagnostics Created: 04/Sep/11  Updated: 16/Jun/13

Status: Open
Project: core.match
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: David Nolen Assignee: David Nolen
Resolution: Unresolved Votes: 0
Labels: None


 Description   

Communicate to the user precisely what failed to match. Conversation here: http://groups.google.com/group/clojure/browse_thread/thread/675456fba1712214. We adopt the behavior of condp since that is closer to what match does and will do (predicate dispatch)



 Comments   
Comment by David Nolen [ 05/Sep/11 10:40 AM ]

Continuing the conversation from GitHub - concerning your changes, we should probably show what current occurrence failed to match as well as the breadcrumb.

Comment by David Nolen [ 26/Sep/11 7:10 AM ]

Matching diagnostics will be complicated by MATCH-1. Clojure doesn't yet support simple data conveying exceptions. Will probably have to use a combination of proxy and definterface.

Comment by Ambrose Bonnaire-Sergeant [ 30/Sep/11 4:39 AM ]

I haven't yet kept up with your backtracking changes, and I just noticed this conversation, so I'll have to have another look at diagnostics with backtracking.

Comment by David Nolen [ 16/Jun/13 1:57 PM ]

Lowering priority. Happy to take a patch, but I don't think I'll be looking into this myself in the near future.





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