abstract class DefaultErrorBuilder extends ErrorBuilder[String]
This class us used to build Parsley's default error messages.
While it compiles with the ErrorBuilder
typeclass, it should not
be considered a stable contract: the formatting can be changed at any
time and without notice. The API, however, will remain stable.
- Source
- DefaultErrorBuilder.scala
- Since
3.0.0
- Note
this class is abstract as it does not implement
unexpectedToken
: when creating an instance mix-in an appropriate token extractor fromparsley.errors.tokenextractors
.
- Grouped
- Alphabetic
- By Inheritance
- DefaultErrorBuilder
- ErrorBuilder
- AnyRef
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- Public
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Instance Constructors
- new DefaultErrorBuilder()
Type Members
- type EndOfInput = String
Represents the end of the input.
Represents the end of the input.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- type ErrorInfoLines = Seq[String]
The representation type of the main body within the error message.
The representation type of the main body within the error message.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- type ExpectedItems = Option[String]
The representation of all the different possible tokens that could have prevented an error.
The representation of all the different possible tokens that could have prevented an error.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- type ExpectedLine = Option[String]
The representation of the information regarding the solving tokens.
The representation of the information regarding the solving tokens.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- type Item = String
The base type of
Raw
,Named
andEndOfInput
that represents the individual items within the error.The base type of
Raw
,Named
andEndOfInput
that represents the individual items within the error.- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- type LineInfo = Seq[String]
The representation of the line of input where the error occurred.
The representation of the line of input where the error occurred.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- type Message = String
The representation of a reason or a message generated by the parser.
The representation of a reason or a message generated by the parser.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- type Messages = Seq[Message]
The representation of the combined reasons or failure messages from the parser.
The representation of the combined reasons or failure messages from the parser.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- type Named = String
This represents "named" tokens, which have been provided with a label.
This represents "named" tokens, which have been provided with a label.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- type Position = String
The representation type of position information within the generated message.
The representation type of position information within the generated message.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- type Raw = String
This represents "raw" tokens, where are those without labels: they come direct from the input, or the characters that the parser is trying to read.
This represents "raw" tokens, where are those without labels: they come direct from the input, or the characters that the parser is trying to read.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- type Source = Option[String]
The representation of the file information.
The representation of the file information.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- type UnexpectedLine = Option[String]
The representation of the information regarding the problematic token.
The representation of the information regarding the problematic token.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
Abstract Value Members
- abstract def unexpectedToken(cs: Iterable[Char], amountOfInputParserWanted: Int, lexicalError: Boolean): Token
Extracts an unexpected token from the remaining input.
Extracts an unexpected token from the remaining input.
When a parser fails, by default an error reports an unexpected token of a specific width. This works well for some parsers, but often it is nice to have the illusion of a dedicated lexing pass: instead of reporting the next few characters as unexpected, an unexpected token can be reported instead. This can take many forms, for instance trimming the token to the next whitespace, only taking one character, or even trying to lex a token out of the stream.
This method can be easily implemented by mixing in an appropriate token extractor from
parsley.errors.tokenextractors
into this builder.- cs
the remaining input at point of failure (this is guaranteed to be non-empty)
- amountOfInputParserWanted
the input the parser tried to read when it failed (this is not guaranteed to be smaller than the length of
cs
)- lexicalError
was this error generated as part of "lexing", or in a wider parser (see
markAsToken
)- returns
a token extracted from
cs
that will be used as part of the unexpected message.
- Definition Classes
- ErrorBuilder
- Since
4.0.0
Concrete Value Members
- final def !=(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- final def ##: Int
- Definition Classes
- AnyRef → Any
- final def ==(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- final def asInstanceOf[T0]: T0
- Definition Classes
- Any
- def clone(): AnyRef
- Attributes
- protected[lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.CloneNotSupportedException]) @native()
- def combineExpectedItems(alts: Set[Item]): ExpectedItems
Details how to combine the various expected items into a single representation.
Details how to combine the various expected items into a single representation.
- alts
The possible items that fix the error
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- def combineMessages(alts: Seq[Message]): Messages
Details how to combine any reasons or messages generated within a single error.
Details how to combine any reasons or messages generated within a single error. Reasons are used by
vanilla
messages and messages are used byspecialised
messages.- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- val endOfInput: EndOfInput
Value that represents the end of the input in the error message.
Value that represents the end of the input in the error message.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- final def eq(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
- def equals(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef → Any
- def expected(alts: ExpectedItems): ExpectedLine
Describes how to handle the information about the tokens that could have avoided the error.
Describes how to handle the information about the tokens that could have avoided the error.
- alts
the tokens that could have prevented the error (see the
combineExpectedItems
method).
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- def finalize(): Unit
- Attributes
- protected[lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.Throwable])
- def format(pos: Position, source: Source, lines: ErrorInfoLines): String
This is the top level function, which finally compiles all the formatted sub-parts into a finished value of type
Err
.This is the top level function, which finally compiles all the formatted sub-parts into a finished value of type
Err
.- pos
this is the representation of the position of the error in the input (see the
pos
method).- source
this is the representation of the filename, if it exists (see the
source
method).- lines
this is the main body of the error message (see
vanillaError
orspecialisedError
methods).- returns
the final assembled error message.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- final def getClass(): Class[_ <: AnyRef]
- Definition Classes
- AnyRef → Any
- Annotations
- @native()
- def hashCode(): Int
- Definition Classes
- AnyRef → Any
- Annotations
- @native()
- final def isInstanceOf[T0]: Boolean
- Definition Classes
- Any
- def lineInfo(line: String, linesBefore: Seq[String], linesAfter: Seq[String], errorPointsAt: Int, errorWidth: Int): LineInfo
Describes how to format the information about the line that the error occured on.
Describes how to format the information about the line that the error occured on.
- line
the full line of input that produced this error message.
- linesBefore
the lines of input just before the one that produced this message (up to
numLinesBefore
).- linesAfter
the lines of input just after the one that produced this message (up to
numLinesAfter
).- errorPointsAt
the offset into the line that the error points at.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- def message(msg: String): Message
Describes how to represent the messages produced by the
fail
combinator (or any that are implemented using it).Describes how to represent the messages produced by the
fail
combinator (or any that are implemented using it).- msg
the message produced by the parser.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- def named(item: String): Named
Formats a named item generated by a label.
Formats a named item generated by a label.
- item
the name given to the label.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- final def ne(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
- final def notify(): Unit
- Definition Classes
- AnyRef
- Annotations
- @native()
- final def notifyAll(): Unit
- Definition Classes
- AnyRef
- Annotations
- @native()
- val numLinesAfter: Int
The number of lines of input to request after an error occured.
The number of lines of input to request after an error occured.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- val numLinesBefore: Int
The number of lines of input to request before an error occured.
The number of lines of input to request before an error occured.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- def pos(line: Int, col: Int): Position
Formats a position into the representation type given by
Position
.Formats a position into the representation type given by
Position
.- line
the line the error occurred at.
- col
the column the error occurred at.
- returns
a representation of the position.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- def raw(item: String): Raw
Formats a raw item generated by either the input string or a input reading combinator without a label.
Formats a raw item generated by either the input string or a input reading combinator without a label.
- item
the raw, unprocessed input.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- def reason(reason: String): Message
Describes how to represent the reasons behind a parser fail.
Describes how to represent the reasons behind a parser fail. These reasons originate from the
explain
combinator.- reason
the reason produced by the parser.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- def source(sourceName: Option[String]): Source
Formats the name of the file if it exists into the type give by
Source
Formats the name of the file if it exists into the type give by
Source
- sourceName
the source name of the file, if any.
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- def specialisedError(msgs: Messages, lines: LineInfo): ErrorInfoLines
Specialised errors are triggered by
fail
and any combinators that are implemented in terms offail
.Specialised errors are triggered by
fail
and any combinators that are implemented in terms offail
. These errors take precedence over the vanilla errors, and contain less, more specialised, information- msgs
information detailing the error (see the
combineMessages
method).
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- final def synchronized[T0](arg0: => T0): T0
- Definition Classes
- AnyRef
- def toString(): String
- Definition Classes
- AnyRef → Any
- def unexpected(item: Option[Item]): UnexpectedLine
Describes how to handle the (potentially missing) information about what token(s) caused the error.
Describes how to handle the (potentially missing) information about what token(s) caused the error.
- item
The
Item
that caused this error
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- def vanillaError(unexpected: UnexpectedLine, expected: ExpectedLine, reasons: Messages, lines: LineInfo): ErrorInfoLines
Vanilla errors are those produced such that they have information about both
expected
andunexpected
tokens.Vanilla errors are those produced such that they have information about both
expected
andunexpected
tokens. These are usually the default, and are not produced byfail
(or any derivative) combinators.- unexpected
information about which token(s) caused the error (see the
unexpected
method).- expected
information about which token(s) would have avoided the error (see the
expected
method).- reasons
additional information about why the error occured (see the
combineMessages
method).
- Definition Classes
- DefaultErrorBuilder → ErrorBuilder
- final def wait(): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
- final def wait(arg0: Long, arg1: Int): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
- final def wait(arg0: Long): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException]) @native()
Top-Level Formatting
These methods help assembly the final products of the error messages. The format
method will return the desired Err
types,
whereas specialisedError
and vanillaError
both assemble an ErrorInfoLines
that the format
method can consume.
Error Preamble
These methods control the formatting of the preamble of an error message, which is the position and source info.
These are then consumed by format
itself.
Contextual Input Lines
These methods control how many lines of input surrounding the error are requested, and direct how these should be put
together to form a LineInfo
.
Shared Components
These methods control any components or structure shared by both types of messages. In particular, the representation of reasons and messages is shared, as well as how they are combined together to form a unified block of content lines.
Specialised-Specific Components
These methods control the Specialised-specific components, namely the formatting of a bespoke error message.
Vanilla-Specific Components
These methods control the Vanilla-specific error components, namely how expected error items
should be combined, how to format the unexpected line, and how to format reasons generated from
explain
.
Error Items
These methods control how error items within Vanilla errors are formatted. These are either
the end of input, a named label generated by the label
combinator,
or a raw piece of input intrinsically associated with a combinator.
This is the documentation for Parsley.
Package structure
The parsley package contains the
Parsley
class, as well as theResult
,Success
, andFailure
types. In addition to these, it also contains the following packages and "modules" (a module is defined as being an object which mocks a package):parsley.Parsley
contains the bulk of the core "function-style" combinators.parsley.combinator
contains many helpful combinators that simplify some common parser patterns.parsley.character
contains the combinators needed to read characters and strings, as well as combinators to match specific sub-sets of characters.parsley.debug
contains debugging combinators, helpful for identifying faults in parsers.parsley.extension
contains syntactic sugar combinators exposed as implicit classes.parsley.io
contains extension methods to run parsers with input sourced from IO sources.parsley.expr
contains the following sub modules:parsley.expr.chain
contains combinators used in expression parsingparsley.expr.precedence
is a builder for expression parsers built on a precedence table.parsley.expr.infix
contains combinators used in expression parsing, but with more permissive types than their equivalents inchain
.parsley.expr.mixed
contains combinators that can be used for expression parsing, but where different fixities may be mixed on the same level: this is rare in practice.parsley.implicits
contains several implicits to add syntactic sugar to the combinators. These are sub-categorised into the following sub modules:parsley.implicits.character
contains implicits to allow you to use character and string literals as parsers.parsley.implicits.combinator
contains implicits related to combinators, such as the ability to make any parser into aParsley[Unit]
automatically.parsley.implicits.lift
enables postfix application of the lift combinator onto a function (or value).parsley.implicits.zipped
enables boths a reversed form of lift where the function appears on the right and is applied on a tuple (useful when type inference has failed) as well as a.zipped
method for building tuples out of several combinators.parsley.errors
contains modules to deal with error messages, their refinement and generation.parsley.errors.combinator
provides combinators that can be used to either produce more detailed errors as well as refine existing errors.parsley.errors.tokenextractors
provides mixins for common token extraction strategies during error message generation: these can be used to avoid implementingunexpectedToken
in theErrorBuilder
.parsley.lift
contains functions which lift functions that work on regular types to those which now combine the results of parsers returning those same types. these are ubiquitous.parsley.ap
contains functions which allow for the application of a parser returning a function to several parsers returning each of the argument types.parsley.registers
contains combinators that interact with the context-sensitive functionality in the form of registers.parsley.token
contains theLexer
class that provides a host of helpful lexing combinators when provided with the description of a language.parsley.genericbridges
contains some basic implementations of the Parser Bridge pattern (see Design Patterns for Parser Combinators in Scala, or the parsley wiki): these can be used before more specialised generic bridge traits can be constructed.