java.lang.Object
- fj.parser.Parser<I,A,E>

```
public final class Parser<I,A,E>
extends java.lang.Object
```
A parser is a function that takes some input (I) and produces either an error (E) or a parse result (A) and the remainder of the input.

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`static class`	`Parser.CharsParser`	Parsers that accept `Stream<Character>` input.
`static class`	`Parser.StreamParser`	Parsers that accept `Stream` input.

Field Summary

Fields
Modifier and Type Field Description

private F<I,Validation<E,Result<I,A>>> f

Constructor Summary

Constructors
Modifier Constructor Description

private Parser(F<I,Validation<E,Result<I,A>>> f)

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`<B> Parser<I,B,E>`	`apply(Parser<I,F<A,B>,E> p)`	Performs function application within a parser.
`<B> Parser<I,B,E>`	`bind(F<A,Parser<I,B,E>> f)`	Binds the given function across the parser with a final join.
`<B,C> Parser<I,C,E>`	`bind(Parser<I,B,E> pb, F<A,F<B,C>> f)`	Binds the given function across the parsers with a final join.
`<B,C,D> Parser<I,D,E>`	`bind(Parser<I,B,E> pb, Parser<I,C,E> pc, F<A,F<B,F<C,D>>> f)`	Binds the given function across the parsers with a final join.
`<B,C,D,E$> Parser<I,E$,E>`	`bind(Parser<I,B,E> pb, Parser<I,C,E> pc, Parser<I,D,E> pd, F<A,F<B,F<C,F<D,E$>>>> f)`	Binds the given function across the parsers with a final join.
`<B,C,D,E$,F$> Parser<I,F$,E>`	`bind(Parser<I,B,E> pb, Parser<I,C,E> pc, Parser<I,D,E> pd, Parser<I,E$,E> pe, F<A,F<B,F<C,F<D,F<E$,F$>>>>> f)`	Binds the given function across the parsers with a final join.
`<B,C,D,E$,F$,G> Parser<I,G,E>`	`bind(Parser<I,B,E> pb, Parser<I,C,E> pc, Parser<I,D,E> pd, Parser<I,E$,E> pe, Parser<I,F$,E> pf, F<A,F<B,F<C,F<D,F<E$,F<F$,G>>>>>> f)`	Binds the given function across the parsers with a final join.
`<B,C,D,E$,F$,G,H> Parser<I,H,E>`	`bind(Parser<I,B,E> pb, Parser<I,C,E> pc, Parser<I,D,E> pd, Parser<I,E$,E> pe, Parser<I,F$,E> pf, Parser<I,G,E> pg, F<A,F<B,F<C,F<D,F<E$,F<F$,F<G,H>>>>>>> f)`	Binds the given function across the parsers with a final join.
`<B,C,D,E$,F$,G,H,I$> Parser<I,I$,E>`	`bind(Parser<I,B,E> pb, Parser<I,C,E> pc, Parser<I,D,E> pd, Parser<I,E$,E> pe, Parser<I,F$,E> pf, Parser<I,G,E> pg, Parser<I,H,E> ph, F<A,F<B,F<C,F<D,F<E$,F<F$,F<G,F<H,I$>>>>>>>> f)`	Binds the given function across the parsers with a final join.
`static <I,A,E> Parser<I,A,E>`	`fail(E e)`	Returns a parser that always fails with the given error.
`Parser<I,A,E>`	`filter(F<A,java.lang.Boolean> f, E e)`	Returns a parser that fails with the given error if the result value does not meet the given predicate.
`<B> Parser<I,B,E>`	`map(F<A,B> f)`	Maps the given result type across this parser.
`<K> Parser<I,A,K>`	`mapError(F<E,K> f)`	Maps the given function across this parser's error.
`Parser<I,Unit,E>`	`not(E e)`	Returns a parser that negates this parser.
`Parser<I,Unit,E>`	`not(F0<E> e)`	Returns a parser that negates this parser.
`Parser<I,A,E>`	`or(F0<Parser<I,A,E>> alt)`	Returns a parser that tries this parser and if it fails, then tries the given parser.
`Parser<I,A,E>`	`or(F0<Parser<I,A,E>> alt, Semigroup<E> s)`	Returns a parser that tries this parser and if it fails, then tries the given parser.
`Parser<I,A,E>`	`or(Parser<I,A,E> alt)`	Returns a parser that tries this parser and if it fails, then tries the given parser.
`Parser<I,A,E>`	`or(Parser<I,A,E> alt, Semigroup<E> s)`	Returns a parser that tries this parser and if it fails, then tries the given parser.
`Validation<E,Result<I,A>>`	`parse(I i)`	Parses the input to produce a result or error.
`static <I,A,E> Parser<I,A,E>`	`parser(F<I,Validation<E,Result<I,A>>> f)`	Returns a parser that computes using the given function.
`Parser<I,Stream<A>,E>`	`repeat()`	Returns a parser that repeats application of this parser zero or many times.
`Parser<I,Stream<A>,E>`	`repeat1()`	Returns a parser that repeats application of this parser one or many times.
`static <I,A,E> Parser<I,List<A>,E>`	`sequence(List<Parser<I,A,E>> ps)`	Sequence the list of parsers through `bind(fj.F<A, fj.parser.Parser<I, B, E>>)`.
`<B> Parser<I,B,E>`	`sequence(Parser<I,B,E> p)`	Binds anonymously, ignoring the result value.
`static <I,A,E> Parser<I,A,E>`	`value(A a)`	Constructs a parser that always returns the given value.
`<Z> Parser<Z,A,E>`	`xmap(F<I,Z> f, F<Z,I> g)`	Maps the parse input type through an invariant functor.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

f

private final F<I,Validation<E,Result<I,A>>> f

Constructor Detail

Parser

private Parser(F<I,Validation<E,Result<I,A>>> f)

Method Detail

parse
```
public Validation<E,Result<I,A>> parse(I i)
```
Parses the input to produce a result or error.

Parameters:

i - The input to parse.

Returns:

A parse result with the remaining input or an error.

xmap
```
public <Z> Parser<Z,A,E> xmap(F<I,Z> f,
                                          F<Z,I> g)
```
Maps the parse input type through an invariant functor.

Parameters:

f - The function to covariant map.

g - The function to contra-variant map.

Returns:

A parser with the new input type.

map
```
public <B> Parser<I,B,E> map(F<A,B> f)
```
Maps the given result type across this parser.

Parameters:

f - The function to map.

Returns:

A parser with the new result type.

filter
```
public Parser<I,A,E> filter(F<A,java.lang.Boolean> f,
                                        E e)
```
Returns a parser that fails with the given error if the result value does not meet the given predicate.

Parameters:

f - The predicate to filter on.

e - The error to in the event that the predicate is not met.

Returns:

A parser that fails with the given error if the result value does not meet the given predicate.

bind
```
public <B> Parser<I,B,E> bind(F<A,Parser<I,B,E>> f)
```
Binds the given function across the parser with a final join.

Parameters:

f - The function to apply to the element of this parser.

Returns:

A new parser after performing the map, then final join.

bind
```
public <B,C> Parser<I,C,E> bind(Parser<I,B,E> pb,
                                                  F<A,F<B,C>> f)
```
Binds the given function across the parsers with a final join.

Parameters:

f - The function to apply to the element of the parsers.

pb - A given parser to bind the given function with.

Returns:

A new parser after performing the map, then final join.