Package jjparse

Class Parsing.Failure<T>

java.lang.Object

Parsing<I>.jjparse.Parsing.Result<T>

jjparse.Parsing.Failure<T>

Type Parameters:

T - The covariant type of the parsed value, which is unused in case of a Parsing.Failure.

Direct Known Subclasses:

Parsing.Abort, Parsing.Error

Enclosing class:

Parsing<I>

public abstract sealed class Parsing.Failure<T>
extends Parsing<I>.Result<T>
permits Parsing<I>.Error<T>, Parsing<I>.Abort<T>

Represents a Parsing.Result which indicates a parse failure.

Instead of the parsed value, a Parsing.Failure only carries an error message that describes the failure in detail. Moreover, a Parsing.Failure comes in two variants:

• Parsing.Error: A recoverable kind of Parsing.Failure that may trigger backtracking during parsing.
• Parsing.Abort: A fatal kind of Parsing.Failure that does not trigger backtracking and aborts parsing.

Note: This class is intended to be immutable and hence covariant in its type parameter.

Author:

Björn Lötters

See Also:

• Parsing.Result
• Parsing.Success
• Parsing.Error
• Parsing.Abort

Field Summary

Fields

Modifier and Type	Field	Description
final String	message	The error message that describes this Parsing.Failure in more detail.

Fields inherited from class jjparse.Parsing.Result

rest

Constructor Summary

Constructors

Constructor	Description
Failure(String message, Input<? extends I> rest)	The base constructor for a Parsing.Failure.

Method Summary

Modifier and Type	Method	Description
<U> Parsing<I>.Result<U>	flatMap(Function<T,Parsing<I>.Result<U>> function)	Maps the value of this Parsing.Result in case it is a Parsing.Success to another Parsing.Result using the provided Function and flattens the nested Parsing.Result.
static String	format(Input<?> input, Description description)	Format an error message for the provided Input and Description.
Optional<T>	get()	Returns the value of this Parsing.Result, if it is present.
T	getOrFail()	Returns the value of this Parsing.Result or fails with an exception, if it is not present.
final boolean	isFailure()	Checks whether this Parsing.Result is a Parsing.Failure.
abstract boolean	isFatal()	Checks whether this Parsing.Failure is fatal in the sense that no backtracking shall be applied during parsing.
final boolean	isSuccess()	Checks whether this Parsing.Result is a Parsing.Success.
<U> Parsing<I>.Result<U>	map(Function<T,U> function)	Maps the value of this Parsing.Result in case it is a Parsing.Success using the provided Function.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

message

public final String message

The error message that describes this Parsing.Failure in more detail.

Constructor Details

Failure

public Failure(String message,
 Input<? extends I> rest)

The base constructor for a Parsing.Failure.

Parameters:

message - The error message that describes this Parsing.Failure in more detail.

rest - The rest of the Input.

Method Details

get

public Optional<T> get()

Description copied from class: Parsing.Result

Returns the value of this Parsing.Result, if it is present.

Specified by:

get in class Parsing<I>.Result<T>

Returns:

The optional value of this Parsing.Result.

getOrFail

public T getOrFail()
            throws NoSuchElementException

Description copied from class: Parsing.Result

Returns the value of this Parsing.Result or fails with an exception, if it is not present.

Specified by:

getOrFail in class Parsing<I>.Result<T>

Returns:

The value of this Parsing.Result.

Throws:

NoSuchElementException - If this Parsing.Result is not a Parsing.Success.

isFailure

public final boolean isFailure()

Description copied from class: Parsing.Result

Checks whether this Parsing.Result is a Parsing.Failure.

Specified by:

isFailure in class Parsing<I>.Result<T>

Returns:

true if this Parsing.Result is a Parsing.Failure.

isSuccess

public final boolean isSuccess()

Description copied from class: Parsing.Result

Checks whether this Parsing.Result is a Parsing.Success.

Specified by:

isSuccess in class Parsing<I>.Result<T>

Returns:

true if this Parsing.Result is a Parsing.Success.

isFatal

public abstract boolean isFatal()

Checks whether this Parsing.Failure is fatal in the sense that no backtracking shall be applied during parsing.

Returns:

true if this Parsing.Failure is an Parsing.Abort and false if it is an Parsing.Error.

map

public <U> Parsing<I>.Result<U> map(Function<T,U> function)

Description copied from class: Parsing.Result

Maps the value of this Parsing.Result in case it is a Parsing.Success using the provided Function.

Specified by:

map in class Parsing<I>.Result<T>

Type Parameters:

U - The type of the mapped value.

Parameters:

function - The Function used to map the value.

Returns:

A Parsing.Result which contains the mapped value.

flatMap

public <U> Parsing<I>.Result<U> flatMap(Function<T,Parsing<I>.Result<U>> function)

Description copied from class: Parsing.Result

Maps the value of this Parsing.Result in case it is a Parsing.Success to another Parsing.Result using the provided Function and flattens the nested Parsing.Result.

Specified by:

flatMap in class Parsing<I>.Result<T>

Type Parameters:

U - The type of the returned Parsing.Result.

Parameters:

function - The Function used to map the value.

Returns:

The Parsing.Result of the mapped value.

format

public static String format(Input<?> input,
 Description description)

Format an error message for the provided Input and Description.

Parameters:

input - The related Input of the error message.

description - The Description of the Parsing.Parser that failed.

Returns:

A formatted error message that provides details about the location and kind of the error.