Am Sonntag, 13. Februar 2005 10:16 schrieb Dmitri Pissarenko:
Hello!
Thanks for your answer!
I've tried that and wrote
<code-snippet> do... let classifiedImagesWithData = ((return trainingSet) >>= readClassifiedImages) ciwd <- (sequence classifiedImagesWithData) let allImages = (getImages ciwd) </code-snippet>
Now, I get the error
<error> Compiling ExperimentalYaleDb ( ExperimentalYaleFaceDb.hs, interpreted )
ExperimentalYaleFaceDb.hs:41: Couldn't match `[]' against `IO' Expected type: [[a]] Inferred type: [IO (ClassifiedImage, Image)] In the first argument of `sequence', namely `classifiedImagesWithData' In a 'do' expression: ciwd <- (sequence classifiedImagesWithData) Failed, modules loaded: TestLik, Lik, HUnit, HUnitText, HUnitBase, HUnitLang. </error>
at line
ciwd <- (sequence classifiedImagesWithData)
Are there any other options?
Thanks in advance
Dmitri Pissarenko
PS: Maybe the error is rooted in code parts other than those given here. In the attachment there is the code of the main program (ExperimentalYaleFaceDb.hs) and the function definitions (Lik.hs).
The error is in the code line above, you can't write trainingSet :: [ClassifiedImage] by itself in a do statement. With -fglasgow-exts, you could write let (trainingSet :: [ClassifiedImage]) = ..., though there's no need for this type signature. Thus, ghci had no more complaints.
-- Dmitri Pissarenko Software Engineer http://dapissarenko.com
HTH, Daniel