Difference between revisions of "HXT/Practical/Ebay1"
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(Munging from an ebay feedback page) |
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| − | < |
+ | <haskell> |
{-# LANGUAGE Arrows, NoMonomorphismRestriction, ParallelListComp #-} |
{-# LANGUAGE Arrows, NoMonomorphismRestriction, ParallelListComp #-} |
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module Main where |
module Main where |
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| − | import Text.XML.HXT. |
+ | import Text.XML.HXT.Core hiding (deep) |
import Data.List (nub,sort,isPrefixOf,transpose,groupBy) |
import Data.List (nub,sort,isPrefixOf,transpose,groupBy) |
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deep f = f `orElse` (getChildren >>> deep f) -- deep redefinition to allow a broader signature |
deep f = f `orElse` (getChildren >>> deep f) -- deep redefinition to allow a broader signature |
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| + | split "" = [] |
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| − | split = map (dropWhile p) . groupBy (const (not . p)) where p = (=='/') |
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| + | split xs = a : split (drop 1 b) where (a,b) = break (=='/') xs |
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| + | |||
through = (getChildren >>>) . foldr1 (/>). map hasName . split |
through = (getChildren >>>) . foldr1 (/>). map hasName . split |
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-- contains = (getChildren >>>). foldr1 (</). (map hasName) |
-- contains = (getChildren >>>). foldr1 (</). (map hasName) |
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| Line 30: | Line 32: | ||
dst = "feedback.report.html" |
dst = "feedback.report.html" |
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| + | main = runX ( readDocument [ withParseHTML yes |
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| − | unicoding= (a_encoding, unicodeString) |
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| + | , withInputEncoding unicodeString |
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| − | nowarnings = (a_issue_warnings,v_0) |
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| + | , withWarnings no |
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| − | |||
| + | ] src |
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| − | main = runX ( readDocument [(a_parse_html, v_1),unicoding,nowarnings] src |
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>>> root [] [deep getFeedbackAndValue] |
>>> root [] [deep getFeedbackAndValue] |
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| − | >>> writeDocument |
+ | >>> writeDocument |
| + | [ withIndent yes |
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| + | , withOutputEncoding unicodeString |
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| + | ] dst |
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) |
) |
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| − | </ |
+ | </haskell> |
| + | |||
| + | Note that the use of groupBy in defining 'split' abuses the implementation details of 'groupBy' which are not guaranteed by its definition in the Haskell 98 standard report. |
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Latest revision as of 17:09, 11 October 2011
{-# LANGUAGE Arrows, NoMonomorphismRestriction, ParallelListComp #-}
module Main where
import Text.XML.HXT.Core hiding (deep)
import Data.List (nub,sort,isPrefixOf,transpose,groupBy)
deep f = f `orElse` (getChildren >>> deep f) -- deep redefinition to allow a broader signature
split "" = []
split xs = a : split (drop 1 b) where (a,b) = break (=='/') xs
through = (getChildren >>>) . foldr1 (/>). map hasName . split
-- contains = (getChildren >>>). foldr1 (</). (map hasName)
mkReport = mkelem "p" [] . map constA
{- The datas we are munging is unstructured
- Every feedback is spanned on two contigous rows of a big table
- We cannot catch the all data in a match, so we use listA to have the two single-row lists
- and then zip them to rebuild the data.
-}
getFeedbackAndValue =
hasName "table"
>>> hasAttrValue "class" (=="fbOuter")
/> hasName "tbody"
>>> proc table -> do
feedbacks <- listA (through "tr/td/img") -< table
values <- listA (through "tr/td" /> hasText (isPrefixOf "EUR")) -< table
catA (map mkReport $ transpose [values,feedbacks]) -<< ()
src = "feedback.example.html"
dst = "feedback.report.html"
main = runX ( readDocument [ withParseHTML yes
, withInputEncoding unicodeString
, withWarnings no
] src
>>> root [] [deep getFeedbackAndValue]
>>> writeDocument
[ withIndent yes
, withOutputEncoding unicodeString
] dst
)
Note that the use of groupBy in defining 'split' abuses the implementation details of 'groupBy' which are not guaranteed by its definition in the Haskell 98 standard report.