Haskell語言學習筆記（52）正則表達式

Text.Regex.PCRE.Heavy

$ brew install pcre
$ cabal install pcre-heavy
Installed pcre-heavy-1.0.0.2
Prelude> :m +Text.Regex.PCRE.Heavy
Prelude Text.Regex.PCRE.Heavy>

Prelude Text.Regex.PCRE.Heavy> :set -XQuasiQuotes
Prelude Text.Regex.PCRE.Heavy> :set -XFlexibleContexts
Prelude Text.Regex.PCRE.Heavy> "123-4567-89" =~ [re|\d{3}-(\d{4})-\d{2}|]
True
Prelude Text.Regex.PCRE.Heavy> scan [re|\d{3}-(\d{4})-\d{2}|] "123-4567-89"
[("123-4567-89",["4567"])]
Prelude Text.Regex.PCRE.Heavy> scanRanges [re|\d{3}-(\d{4})-\d{2}|] "123-4567-89"
[((0,11),[(4,8)])]
Prelude Text.Regex.PCRE.Heavy> sub [re|(\d+)-(\d+)-(\d+)|] (\(d1:d2:d3:_) -> d3 ++ "-" ++ d1 ++ "-" ++ d2)  "123-4567-89"
"89-123-4567"
Prelude Text.Regex.PCRE.Heavy> :set -XScopedTypeVariables
Prelude Text.Regex.PCRE.Heavy> sub [re|\d+|] (\(s::String) -> reverse s) "123-4567-89"
"321-4567-89"
Prelude Text.Regex.PCRE.Heavy> gsub [re|\d+|] (\(s::String) -> reverse s) "123-4567-89"
"321-7654-98"
Prelude Text.Regex.PCRE.Heavy> split [re|%(begin|next|end)%|] ("%begin%hello%next%world%end%" :: String)
["","hello","world",""]

• (=~) :: (ConvertibleStrings SBS a, ConvertibleStrings a SBS) => a -> Regex -> Bool
  (=~) 操做符函數檢查字符串是否匹配指定正則表達式。
• scan :: (ConvertibleStrings SBS a, ConvertibleStrings a SBS) => Regex -> a -> [(a, [a])]
  scan 函數查找並返回字符串中全部出現的指定正則表達式。
• scanRanges :: (ConvertibleStrings SBS a, ConvertibleStrings a SBS) => Regex -> a -> [((Int, Int), [(Int, Int)])]
  scanRanges 函數查找字符串中全部出現的指定正則表達式，返回出現的全部位置。
• sub :: (ConvertibleStrings SBS a, ConvertibleStrings a SBS, RegexReplacement r) => Regex -> r -> a -> a
  sub 函數替換字符串中第一次出現的指定正則表達式。
• gsub :: (ConvertibleStrings SBS a, ConvertibleStrings a SBS, RegexReplacement r) => Regex -> r -> a -> a
  gsub 函數替換字符串中全部出現的指定正則表達式。
• split :: (ConvertibleStrings SBS a, ConvertibleStrings a SBS) => Regex -> a -> [a] split 函數使用指定正則表達式分割字符串。