hlex 1.0.0 → 1.0.1

raw patch · 3 files changed

+24/−16 lines, 3 filesPVP ok

version bump matches the API change (PVP)

API changes (from Hackage documentation)

Files

• CHANGELOG.md +7/−0
• hlex.cabal +1/−1
• src/Hlex.hs +16/−15

@@ -13,3 +13,10 @@ Rename TokenSyntax to GrammarRule  Add Error GrammarRule++### 1.0.1++_2025-10-08, Sebastian Tee_++Update sample program in haddock documentation so that it compiles +successfully when copied and pasted

@@ -1,7 +1,7 @@ cabal-version: 1.12  name:           hlex-version:        1.0.0+version:        1.0.1 synopsis:       Simple Lexer Creation description:    This package provides the tools to create a simple lexer. category:       lexer

@@ -24,7 +24,7 @@ import Data.Maybe (maybeToList)  -- | Exception thrown when a 'Lexer' encounters an error when lexxing a string.-data LexException +data LexException   = UnmatchedException -- ^ Exception thrown when a substring cannot be matched.     Int -- ^ The line number where the substring that couldn't be lexed is located.     Int -- ^ The column where the substring that couldn't be lexed is located.@@ -100,39 +100,40 @@ Here is an example module for a simple language.  @-  module ExampleLang+module ExampleLang        ( MyToken(..) -- Export the language's tokens and the lexer        , myLexer        ) where -  import Hlex+import Hlex -  data MyToken = Ident String -- String identifier token+data MyToken = Ident String   -- String identifier token                | Number Float -- Number token and numeric value+               | Str String   -- Enquoted String literal                | Assign       -- Assignment operator token                deriving(Show) -  myGrammar :: Grammar MyToken-  myGrammar = [ Error "\"[^\"]*\n" "Can't have a new line in a string"        -- Return Exception when a new line occurs in a string-              , Tokenize "\"[^\"]*\"" $ Str . init . tail                     -- Encode string and strip the containing quotes-              , JustToken "=" Assign                                       -- "=" Operator becomes the assign token-              , Tokenize "[a-zA-Z]+" (\match -> Ident match)                -- Identifier token with string-              , Tokenize "[0-9]+(\\.[0-9]+)?" (\match -> Number (read match) -- Number token with the parsed numeric value stored as a Float-              , Skip "[ \\n\\r\\t]+"                                          -- Skip whitespace+myGrammar :: Grammar MyToken+myGrammar = [ Error "\\"[^\\"]*\n" "Can't have a new line in a string"         -- Return Exception when a new line occurs in a string+              , Tokenize "\\"[^\\"]*\\"" $ Str . init . tail                   -- Encode string and strip the containing quotes+              , JustToken "=" Assign                                        -- "=" Operator becomes the assign token+              , Tokenize "[a-zA-Z]+" Ident                                  -- Identifier token with string+              , Tokenize "[0-9]+(\\\\.[0-9]+)?" $ Number . read               -- Number token with the parsed numeric value stored as a Float+              , Skip "[ \\n\\r\\t]+"                                           -- Skip whitespace               ] -  myLexer :: Lexer MyToken-  myLexer = hlex myGrammar -- hlex turns a Grammar into a Lexer+myLexer :: Lexer MyToken+myLexer = hlex myGrammar -- hlex turns a Grammar into a Lexer @  Here is the lexer being used on a simple program. ->>> lexer "x = 1.2"+>>> myLexer "x = 1.2" Right [Ident "x", Assign, Number 1.2]  Here is the lexer being used on an program with a syntax error. ->>> lexer "x = \"a\nb\""+>>> myLexer "x = \"a\nb\"" Left (MatchedException 1 5 "\"a\n" "Can't have a new line in a string")  The lexer uses 'Either'. Right means the lexer successfully parsed the program to a list of MyTokens.