attoparsec-0.11.1.0: Fast combinator parsing for bytestrings and text

Portability portable experimental bos@serpentine.com None

Data.Attoparsec.Combinator

Description

Useful parser combinators, similar to those provided by Parsec.

Synopsis

Documentation

choice :: Alternative f => [f a] -> f aSource

`choice ps` tries to apply the actions in the list `ps` in order, until one of them succeeds. Returns the value of the succeeding action.

count :: Monad m => Int -> m a -> m [a]Source

Apply the given action repeatedly, returning every result.

option :: Alternative f => a -> f a -> f aSource

`option x p` tries to apply action `p`. If `p` fails without consuming input, it returns the value `x`, otherwise the value returned by `p`.

``` priority  = option 0 (digitToInt <\$> digit)
```

many' :: MonadPlus m => m a -> m [a]Source

`many' p` applies the action `p` zero or more times. Returns a list of the returned values of `p`. The value returned by `p` is forced to WHNF.

```  word  = many' letter
```

many1 :: Alternative f => f a -> f [a]Source

`many1 p` applies the action `p` one or more times. Returns a list of the returned values of `p`.

```  word  = many1 letter
```

many1' :: MonadPlus m => m a -> m [a]Source

`many1' p` applies the action `p` one or more times. Returns a list of the returned values of `p`. The value returned by `p` is forced to WHNF.

```  word  = many1' letter
```

manyTill :: Alternative f => f a -> f b -> f [a]Source

`manyTill p end` applies action `p` zero or more times until action `end` succeeds, and returns the list of values returned by `p`. This can be used to scan comments:

```  simpleComment   = string "<!--" *> manyTill anyChar (try (string "-->"))
```

Note the overlapping parsers `anyChar` and `string "<!--"`, and therefore the use of the `try` combinator.

manyTill' :: MonadPlus m => m a -> m b -> m [a]Source

`manyTill' p end` applies action `p` zero or more times until action `end` succeeds, and returns the list of values returned by `p`. This can be used to scan comments:

```  simpleComment   = string "<!--" *> manyTill' anyChar (try (string "-->"))
```

Note the overlapping parsers `anyChar` and `string "<!--"`, and therefore the use of the `try` combinator. The value returned by `p` is forced to WHNF.

sepBy :: Alternative f => f a -> f s -> f [a]Source

`sepBy p sep` applies zero or more occurrences of `p`, separated by `sep`. Returns a list of the values returned by `p`.

``` commaSep p  = p `sepBy` (symbol ",")
```

sepBy' :: MonadPlus m => m a -> m s -> m [a]Source

`sepBy' p sep` applies zero or more occurrences of `p`, separated by `sep`. Returns a list of the values returned by `p`. The value returned by `p` is forced to WHNF.

``` commaSep p  = p `sepBy'` (symbol ",")
```

sepBy1 :: Alternative f => f a -> f s -> f [a]Source

`sepBy1 p sep` applies one or more occurrences of `p`, separated by `sep`. Returns a list of the values returned by `p`.

``` commaSep p  = p `sepBy1` (symbol ",")
```

sepBy1' :: MonadPlus m => m a -> m s -> m [a]Source

`sepBy1' p sep` applies one or more occurrences of `p`, separated by `sep`. Returns a list of the values returned by `p`. The value returned by `p` is forced to WHNF.

``` commaSep p  = p `sepBy1'` (symbol ",")
```

skipMany :: Alternative f => f a -> f ()Source

Skip zero or more instances of an action.

skipMany1 :: Alternative f => f a -> f ()Source

Skip one or more instances of an action.

eitherP :: Alternative f => f a -> f b -> f (Either a b)Source

Combine two alternatives.