Documentation
¶
Overview ¶
This package provides a number of simple services for accessing and handling chess games in PGN format
Index ¶
- Constants
- type PgnBoard
- type PgnCollection
- func (c *PgnCollection) Add(game PgnGame)
- func (c PgnCollection) Filter(expression string) (*PgnCollection, error)
- func (games *PgnCollection) GamesToWriterFromTemplate(dst io.Writer, templateFile string)
- func (games *PgnCollection) GetGame(index int) PgnGame
- func (games *PgnCollection) GetGames() []PgnGame
- func (c PgnCollection) GetHistogram(spec string) (*PgnHistogram, error)
- func (c PgnCollection) GetPGN(writer io.Writer) error
- func (games *PgnCollection) GetSlice(fields ...any) []any
- func (games *PgnCollection) GetTable(specline string, fields []any) table.Table
- func (games *PgnCollection) GetTagValue(name string) string
- func (games PgnCollection) Len() int
- func (c PgnCollection) Play(plies int, writer io.Writer)
- func (games *PgnCollection) ShowIndex() string
- func (c *PgnCollection) Sort(spec string) (*PgnCollection, error)
- type PgnFile
- type PgnGame
- func (game *PgnGame) Filter(expression string) (bool, error)
- func (game *PgnGame) GetField(field string) string
- func (game *PgnGame) GetLaTeXMovesWithComments() string
- func (game *PgnGame) GetLaTeXMovesWithCommentsTabular(width1, width2 string, nbplies int) (output string)
- func (game *PgnGame) GetPGN() (output string)
- func (game *PgnGame) GetTagValue(name string) (value string, err error)
- func (game *PgnGame) Moves() []PgnMove
- func (game *PgnGame) Outcome() PgnOutcome
- func (game *PgnGame) SetLabel() string
- func (game *PgnGame) Tags() (tags map[string]any)
- type PgnHistogram
- type PgnMove
- type PgnOutcome
Constants ¶
const ( BKING content = -6 + iota BQUEEN BROOK BBISHOP BKNIGHT BPAWN // -1: represent also black pieces BLANK // 0: empty WPAWN // 1: represent also white pieces WKNIGHT WBISHOP WROOK WQUEEN WKING )
The different values of content are shown next. These symbols are intentionally exported so that other people can handle chess boards using the services provided by this package
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type PgnBoard ¶
type PgnBoard struct {
// contains filtered or unexported fields
}
A PgnBoard consists simply of an array of 64 integers. In addition, the location of both kings has to be updated. This information is used to determine whether a piece is pinned or not
func (*PgnBoard) UpdateBoard ¶
The following method updates the contents of the current board after making the given move. In case it is not possible to execute the given move, then an error is returned
type PgnCollection ¶
type PgnCollection struct {
// contains filtered or unexported fields
}
A PgnCollection consists of an arbitrary number of PgnGames
func NewPgnCollection ¶
func NewPgnCollection() PgnCollection
Return an empty collection of PGN games
func (*PgnCollection) Add ¶
func (c *PgnCollection) Add(game PgnGame)
Add the given PgnGame to this collection
func (PgnCollection) Filter ¶
func (c PgnCollection) Filter(expression string) (*PgnCollection, error)
Create a brand new PgnCollection with games found in this collection which satisfy the given expression
func (*PgnCollection) GamesToWriterFromTemplate ¶
func (games *PgnCollection) GamesToWriterFromTemplate(dst io.Writer, templateFile string)
Writes into the specified writer the result of instantiating the given template file with information of all games in this collection. The template acknowledges all tags of a pgngame plus others. For a full description, see the manual.
func (*PgnCollection) GetGame ¶
func (games *PgnCollection) GetGame(index int) PgnGame
Return the index-th game stored in this particular collection. The result is undefined in case an index out of bounds is passed
func (*PgnCollection) GetGames ¶
func (games *PgnCollection) GetGames() []PgnGame
Return all games as instances of PgnGame that are stored in this particular collection
func (PgnCollection) GetHistogram ¶
func (c PgnCollection) GetHistogram(spec string) (*PgnHistogram, error)
Return a histogram defined with the given specification criteria computed over all games in this collection. It returns any error found or nil in case the histogram was successfully computed
func (PgnCollection) GetPGN ¶
func (c PgnCollection) GetPGN(writer io.Writer) error
Write all games in this collection in the specified io.Writer in PGN format. In case it was not possible it returns an error and nil otherwise
func (*PgnCollection) GetSlice ¶
func (games *PgnCollection) GetSlice(fields ...any) []any
This is an auxiliary function used in text/templates to generate slices of strings to be given as argument to other methods
func (*PgnCollection) GetTable ¶
func (games *PgnCollection) GetTable(specline string, fields []any) table.Table
Returns a table according to the specification given in first place. Columns are populated with the tags given in fields. It is intended to be used in ascii table templates
It is intended to be used in LaTeX templates
func (*PgnCollection) GetTagValue ¶
func (games *PgnCollection) GetTagValue(name string) string
This function is used in text/templates and it is the equivalent to the homonym function defined for PgnGame.
It returns the empty string if the given name is not defined as a tag in the first game of this collection and the value of the tag (casted to a string) otherwise. This function assumes that all games within the same collection share the same tags.
It is intended to be used in LaTeX templates
func (PgnCollection) Len ¶
func (games PgnCollection) Len() int
Return the number of items in the collection
func (PgnCollection) Play ¶
func (c PgnCollection) Play(plies int, writer io.Writer)
Play this collection of games on the given writer showing the board repeteadly after the given number of plies on the specified writer, in case it is strictly positive.
func (*PgnCollection) ShowIndex ¶
func (games *PgnCollection) ShowIndex() string
Return an index of the games in this collection. It assumes that each game is properly indexed with labels (with the usage of game.SetLabel ())
It is intended to be used in LaTeX templates
func (*PgnCollection) Sort ¶
func (c *PgnCollection) Sort(spec string) (*PgnCollection, error)
Sort the games in this collection according to the specific criteria which consists of a semicolon separated list of pairs (direction var/bool expr). The direction can be either '<' (ascending order) or '>' (descending order), next either a variable or a bool expression can be used so that games are sorted according to the value of the variable or the result of the evaluation of the bool expr
The result is returned in a brand new collection of Pgn games
type PgnFile ¶
type PgnFile struct {
// contains filtered or unexported fields
}
A PgnFile contains a collection of chess games in PGN format. It stores no information related to the chess games contained in it and it should be used solely for creating a PgnCollection
func NewPgnFile ¶
A new instance of PgnFile can be created just by providing the file path (which is allowed also to contain the character '~'). In case the file does not exist, or it is not a regular file then an error is returned
func (PgnFile) Games ¶
func (f PgnFile) Games() (*PgnCollection, error)
Return all games stored in the PgnFile f as a collection of PgnGames
type PgnGame ¶
type PgnGame struct {
// contains filtered or unexported fields
}
A game consists just of a map that stores information of all PGN tags, the sequence of moves and finally the outcome.
func (*PgnGame) GetField ¶
A field is either a tag of the receiver game, or a value that can be extracted from it (such as "Moves" or "Result")
This function is to be used in LaTeX templates
func (*PgnGame) GetLaTeXMovesWithComments ¶
Produces a LaTeX string with the list of moves of this game along with the different annotations.
This method successively processes the moves in this PgnGame until a comment is found.
It is intended to be used in LaTeX templates
func (*PgnGame) GetLaTeXMovesWithCommentsTabular ¶
func (game *PgnGame) GetLaTeXMovesWithCommentsTabular(width1, width2 string, nbplies int) (output string)
Produces a LaTeX string with a long table showing the moves every nbplies and the chess board
This method successively processes the moves in this PgnGame until a comment is found.
It is intended to be used in LaTeX templates
func (*PgnGame) GetTagValue ¶
Return the value of a specific tag. In case the tag is not found in this game, an error is return along with any data.
It is intended to be used in LaTeX templates
func (*PgnGame) Outcome ¶
func (game *PgnGame) Outcome() PgnOutcome
Return an instance of PgnOutcome with the result of this game
type PgnHistogram ¶
type PgnHistogram struct {
// contains filtered or unexported fields
}
Given a sequence of criteria (either variables or boolean expressions), which might be named, a histogram is implemented as a decision tree where internal nodes store the result of the criteria and lead to other histograms or decision trees until the leaves are reached which simply store the number of occurrences of all variables/boolean expressions from the root to it.
In addition, a histogram contains the total number of observations stored in it so that percentages can be computed for every inner/leaf node
func NewPgnHistogram ¶
func NewPgnHistogram(spec string) (*PgnHistogram, error)
Return a brand new PgnHistogram defined with a string, which consists of a semicolon list of variables/boolean expressions in the form: "<var/expr>+". At least one should be given, and an arbitrary number of them can be specified.
func (*PgnHistogram) Add ¶
func (histogram *PgnHistogram) Add(game PgnGame) error
Updates this histogram with information in the given game, and nil if no error was found
func (PgnHistogram) String ¶
func (histogram PgnHistogram) String() string
Histograms are stringers, so that they can be shown on any writer
type PgnMove ¶
type PgnMove struct {
// contains filtered or unexported fields
}
A PGN move consist of a single ply. For each move the move number, color (with -1 representing black and +1 representing white) and actual move value (in algebraic form) is stored. Additionally, in case that the elapsed move time was present in the PGN file, it is also stored here.
Finally, any combination of moves after the move are combined into the same field (comments). In case various comments were given they are then separated by '\n'.
type PgnOutcome ¶
type PgnOutcome struct {
// contains filtered or unexported fields
}
The outcome of a chess game consists of the score obtained by every player as two float32 numbers such that their sum equals 1. Plausible outcomes are (0, 1), (1, 0) and (0.5, 0.5). In addition, the pair (-1, -1) is considered for those games which are not properly ended
func (PgnOutcome) String ¶
func (outcome PgnOutcome) String() string
Produces a string with information of this outcome as a pair of floating-point numbers
Source Files