diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,30 @@ +Copyright (c) 2013, Mikhail Glushenkov + +All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + + * Redistributions in binary form must reproduce the above + copyright notice, this list of conditions and the following + disclaimer in the documentation and/or other materials provided + with the distribution. + + * Neither the name of Mikhail Glushenkov nor the names of other + contributors may be used to endorse or promote products derived + from this software without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/Setup.hs b/Setup.hs new file mode 100644 --- /dev/null +++ b/Setup.hs @@ -0,0 +1,2 @@ +import Distribution.Simple +main = defaultMain diff --git a/Text/RawString/QQ.hs b/Text/RawString/QQ.hs new file mode 100644 --- /dev/null +++ b/Text/RawString/QQ.hs @@ -0,0 +1,94 @@ +-- | Raw string literals, implemented using Template Haskell's quasiquotation +-- feature. +module Text.RawString.QQ + where + +import Language.Haskell.TH +import Language.Haskell.TH.Quote + +{-| + +A quasiquoter for raw string literals - that is, string literals that don't +recognise the standard escape sequences (such as @\'\\n\'@). Basically, they +make your code more readable by freeing you from the responsibility to escape +backslashes. They are useful when working with regular expressions, DOS/Windows +paths and markup languages (such as XML). + +Don't forget the @LANGUAGE QuasiQuotes@ pragma if you're using this +module in your code. + +Usage: + +@ + ghci> :set -XQuasiQuotes + ghci> import Text.RawString.QQ + ghci> let s = [r|\\w+\@[a-zA-Z_]+?\\.[a-zA-Z]{2,3}|] + ghci> s + \"\\\\w+\@[a-zA-Z_]+?\\\\.[a-zA-Z]{2,3}\" + ghci> [r|C:\\Windows\\SYSTEM|] ++ [r|\\user32.dll|] + \"C:\\\\Windows\\\\SYSTEM\\\\user32.dll\" +@ + +Multiline raw string literals are also supported: + +@ + multiline :: String + multiline = [r|\ + \ + \Auto-generated html formated source\ + \ + \ + \ + \ \ + \|] +@ + +Caveat: since the @\"|]\"@ character sequence is used to terminate the +quasiquotation, you can't use it inside the raw string literal. Use 'rQ' if you +want to embed that character sequence inside the raw string. + +For more on raw strings, see e.g. + + +For more on quasiquotation, see + + +-} +r :: QuasiQuoter +r = QuasiQuoter { + -- Extracted from dead-simple-json. + quoteExp = return . LitE . StringL, + + quotePat = \_ -> fail "illegal raw string QuasiQuote \ + \(allowed as expression only, used as a pattern)", + quoteType = \_ -> fail "illegal raw string QuasiQuote \ + \(allowed as expression only, used as a type)", + quoteDec = \_ -> fail "illegal raw string QuasiQuote \ + \(allowed as expression only, used as a declaration)" +} + +{-| A variant of 'r' that interprets the @\"|~]\"@ sequence as @\"|]\"@. + +Usage: + +@ + ghci> [rQ||~]|~]|] + \"|]|]\" +@ +-} +rQ :: QuasiQuoter +rQ = QuasiQuoter { + quoteExp = return . LitE . StringL . escape, + + quotePat = \_ -> fail "illegal raw string QuasiQuote \ + \(allowed as expression only, used as a pattern)", + quoteType = \_ -> fail "illegal raw string QuasiQuote \ + \(allowed as expression only, used as a type)", + quoteDec = \_ -> fail "illegal raw string QuasiQuote \ + \(allowed as expression only, used as a declaration)" +} + where + escape :: String -> String + escape [] = [] + escape ('|':'~':']':xs) = '|':']':escape xs + escape (x:xs) = x : escape xs diff --git a/examples/RawRegex.hs b/examples/RawRegex.hs new file mode 100644 --- /dev/null +++ b/examples/RawRegex.hs @@ -0,0 +1,27 @@ +module Main + where + +import Text.Regex.Posix +import Text.RawString.QQ + +haystack :: String +haystack = "My e-mail address is user@example.com" + +needle :: String +needle = [r|\w+@[a-zA-Z_]+?\.[a-zA-Z]{2,3}|] + +multiline :: String +multiline = [r| + +Auto-generated html formated source + + + +

+
|]
+
+main :: IO ()
+main = do
+  print multiline
+  print ""
+  print $ ((haystack =~ needle) :: String)
diff --git a/raw-strings-qq.cabal b/raw-strings-qq.cabal
new file mode 100644
--- /dev/null
+++ b/raw-strings-qq.cabal
@@ -0,0 +1,32 @@
+name:                raw-strings-qq
+version:             1.0
+synopsis:            Raw string literals for Haskell.
+description:
+
+    A quasiquoter for raw string literals - that is, string literals that don't
+    recognise the standard escape sequences (such as '\n'). Basically, they make
+    your code more readable by freeing you from the responsibility to escape
+    backslashes. They are useful when working with regular expressions,
+    DOS/Windows paths and markup languages (such as XML).
+    .
+    See @examples/RawRegex.hs@ for a usage example.
+
+homepage:            https://github.com/23Skidoo/raw-strings-qq
+bug-reports:         https://github.com/23Skidoo/raw-strings-qq/issues
+license:             BSD3
+license-file:        LICENSE
+author:              Mikhail Glushenkov
+maintainer:          mikhail.glushenkov@gmail.com
+copyright:           (c) Mikhail Glushenkov 2013
+category:            Text
+build-type:          Simple
+cabal-version:       >=1.8
+extra-source-files:  examples/RawRegex.hs
+
+source-repository head
+  type:     git
+  location: https://github.com/23Skidoo/raw-strings-qq.git
+
+library
+  exposed-modules:     Text.RawString.QQ
+  build-depends:       base <= 10, template-haskell >= 2.5