CHANGELOG.md

Changelog

[Unreleased]

Added

• CLI to access library functions:
• Calculate splits for a given height (with the splits subcommand)
  • As formatted text (default)
  • As CSV (with the --csv flag or -c short flag)
• --version and --help flags
• make-rule-set subcommand to create a JSON string describing a Nim game's rules
  • Use --take-split-never or -n either followed by a number to specify a rule where a player may take a number of coins from a stack without splitting it in the process
  • Likewise, --take-split-optional or -o followed by a number specifies a take rule where splitting is optional
  • The --take-split-always or -a option followed by a number specifies a take rule where splitting is mandatory
  • Using --allow-any-take or -A creates a rule allowing to take an arbitrary number of coins from a stack, followed by a choice from never, optional, or always to specify if splitting is forbidden, optional, or mandatory
  • The yet-to-be-implemented --allow-place or -p option creates a rule which allows the player to place coins on a stack; this option is not yet implemented and does not take any arguments
  • --pretty-print or -P prints the JSON string in a more readable format, with indentation and line breaks
• The nimber subcommand to
  • Calculate the nimber(s) for a (set of) stack(s) of given height(s) (using --print stacks or -p stacks)
  • Calculate the nimber of a position of stacks (using --print position or -p position)
  • Display them both (default, or by using --print both or -p both)
  • Rules are taken with the required --rules or -r flag in the form of a JSON string
  • The --json or -j flag can be used to print the output as JSON instead of plain text
  • Likewise, the --json-pretty or -J flag can be used to print the output as pretty-printed JSON
• Logging support with verbosity controls using --verbose or -v (can be used multiple times), or --quiet or -q (can be used multiple times)

Changed

• Applied many clippy suggestions

[0.1.1] - 2023-02-11

Changed

• Improved readme and documentation
  • Fix links: link to latest to help search engines find the latest version
  • Add a description of the library to the readme
  • Explain how Nim games work

[0.1.0] - 2023-02-11

Added

• Module moves
  • Enum MoveError, a list of possible errors when applying or calculating moves
  • check_move is a function which checks if a move is legal for a given position
  • The function calculate_legal_moves which calculates all legal moves from a given position
  • apply_move is a function which applies a move to a position, changing the position
  • The unsafe version of which is apply_move_unchecked which does not check if the move is legal
• Struct Nimber which represents a nimber and simply wraps a u64
  • Used to avoid confusion of heights and nimbers using the type system
• Enum NimAction which represents a move in a Nim game
• Structs TakeAction and PlaceAction which are used in NimAction
• Enum NimSplit, the result of a split: either Yes with two new stacks or No
• Many unit tests for both the old code, and the new

Changed

• Renamed module algo to nimbers
• Function calculate_nimber_for_height in nimbers
  • Now returns a Nimber instead of a u64
  • Now takes a slice of NimRule instead of a hard-coded vector &Vec<NimRule>
  • Moved internal code to moves::calculate_legal_moves (code deduplication)
• Function calculate_legal_moves
  • Argument stacks was moved from &Vec<Stack> to &[Stack], allowing for an optimization in this calculate_nimber_for_height
  • Same goes for its rules argument, which was moved from &Vec<NimRule> to &[NimRule]
• Changed return type of nimbers::calculate_splits Vec<(u64, u64)> from to Vec<(Stack, Stack)>

Removed

• Removed clear_nimber_cache from nimbers (then named algo)
  • The cache now supports multiple rule sets, so clearing the cache is no longer necessary when the rules change
  • Maybe some kind of cache control will be added in the future to reduce memory usage on demand

Fixed

• Fixed a bug in the way the cache was used, which resulted in incorrect nimbers being returned
  • This was due to the fact that the same cache was used for every rule set
  • Now, a new cache is created for every rule set

[0.0.1] - 2023-01-25

Added

• This is the initial release of NimLib
  • Version 0.0.0 was a placeholder release without any code
  • Version 0.0.1 is the first real release
• Module algo
  • The calculate_nimber_for_height function which calculates the nimber for a given height
  • The calculate_splits function which calculates all possible splits for a given height, accounting for symmetry
  • The module also contains the function clear_nimber_cache which has/had to be called every time the rules changed
• Struct NimStack which represents a stack and simply wraps a u64
• Struct NimRule representing a rule in a Nim game
• Struct NimGame representing a Nim game, containing a list of rules and a list of stacks
• Enum Split, used in NimRule
• Enum TakeSize which is used in NimRule