Re: [web-devel] [Yesod][Persist] Like keyword

True, it *would* be better, but it can't fit in with the way persistent works (AFAICT). Let's say that we're dealing with a persistent entity: Person name String Eq Like age Int I now have a PersonNameLike constructor, *regardless of backend*. I don't really think that throwing an exception will be necessary, however: most likely, backends like redis can just implement this functionality in Haskell itself. Performance won't be great, but those are things you'll need to be aware of. I suppose another possibility would be to allow some kind of generic "add to query" and then you could write whatever kind of where clause you want. Michael 2010/12/22 Max Cantor :

Perhaps instead of throwing an exception, you add a typeclass PersistBackendLikeQuery or something where only backends that can handle like queries provide that typeclass. seems better and much more haskellish than tossing an exception.

Max

On Dec 21, 2010, at 6:43 PM, Michael Snoyman wrote:

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I've also wanted this at times. I'm a little wary of including it, since it is very SQL-specific. On the other hand, it might be reasonable to allow it in, and then non-SQL backends can either ignore it, throw an exception, or try to implement it somehow. Does anyone have any thoughts on this?

Michael

2010/12/21 いとうかつとし :

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Hi continuously another request... I'd like to write "Like" keyword for using as Filter. this isn't supported yet, is this?

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