Snn.rb

SNN (Style Name Notation) implementation for the Ruby language.

SNN (Style Name Notation) is a formal, rule-agnostic naming system for identifying styles in abstract strategy board games such as chess, shōgi, xiangqi, and their many variants. Each style is represented by a canonical, human-readable ASCII name (e.g., "Chess", "Shogi", "Xiangqi", "Minishogi").

This gem implements the SNN Specification v1.0.0, supporting validation, parsing, and comparison of style names.

# In your Gemfile
gem "sashite-snn"

Or install manually:

gem install sashite-snn

require "sashite/snn"

# Parse SNN strings into style name objects
name = Sashite::Snn.parse("Shogi")             # => #<Snn::Name value="Shogi">
name.to_s                                      # => "Shogi"
name.value                                     # => "Shogi"

# Create from string or symbol
name = Sashite::Snn.name("Chess")              # => #<Snn::Name value="Chess">
name = Sashite::Snn::Name.new(:Xiangqi)        # => #<Snn::Name value="Xiangqi">

# Validate SNN strings
Sashite::Snn.valid?("Go9x9")                   # => true
Sashite::Snn.valid?("chess")                   # => false (must start with uppercase)
Sashite::Snn.valid?("3DChess")                 # => false (invalid character)

a = Sashite::Snn.parse("Chess960")
b = Sashite::Snn.parse("Chess960")

a == b                                         # => true
a.same_base_name?(Sashite::Snn.parse("Chess")) # => true if both resolve to same SIN
a.to_s # => "Chess960"

# All names are normalized to a canonical format
name = Sashite::Snn.parse("Minishogi")
name.value                                    # => "Minishogi"
name.to_s                                     # => "Minishogi"

names = %w[Chess Shogi Makruk Antichess Minishogi].map { |n| Sashite::Snn.parse(n) }

# Filter by prefix
names.select { |n| n.value.start_with?("Mini") }.map(&:to_s)
# => ["Minishogi"]

<uppercase-letter>[<lowercase-letter | digit>]*

<snn> ::= <uppercase-letter> <tail>

<tail> ::= ""                                ; Single letter (e.g., "X")
        | <alphanumeric-char> <tail>         ; Extended name

<alphanumeric-char> ::= <lowercase-letter> | <digit>

<uppercase-letter> ::= "A" | "B" | "C" | ... | "Z"
<lowercase-letter> ::= "a" | "b" | "c" | ... | "z"
<digit> ::= "0" | "1" | "2" | "3" | ... | "9"

/\A[A-Z][a-z0-9]*\z/

• Human-readable: Names like "Shogi" or "Chess960" are intuitive and descriptive.
• Canonical: One valid name per game style within a given context.
• ASCII-only: Compatible with all systems.
• Scalable: Supports unlimited distinct names for current and future game variants.

SNN names serve as the formal source for SIN character identifiers. For example:

Multiple SNN names may map to the same SIN character (e.g., "Chess" and "Chess960" both → C), but SNN provides unambiguous naming within broader contexts.

Sashite::Snn.parse("Chess")       # => #<Snn::Name value="Chess">
Sashite::Snn.parse("Chess960")    # => #<Snn::Name value="Chess960">
Sashite::Snn.valid?("Minishogi")  # => true
Sashite::Snn.valid?("miniShogi")  # => false

• Sashite::Snn.valid?(str) – Returns true if the string is valid SNN.
• Sashite::Snn.parse(str) – Returns a Sashite::Snn::Name object.
• Sashite::Snn.name(sym_or_str) – Alias for constructing a name.

• #value – Returns the canonical string value.
• #to_s – Returns the string representation.
• #==, #eql?, #hash – Value-based equality.
• #same_base_name?(other) – Optional helper for SIN mapping equivalence.

# Clone the repository
git clone https://github.com/sashite/snn.rb.git
cd snn.rb

# Install dependencies
bundle install

# Run tests
ruby test.rb

# Generate documentation
yard doc

1. Fork the repository
2. Create a feature branch (git checkout -b feature/new-feature)
3. Add tests for your changes
4. Ensure all tests pass (ruby test.rb)
5. Commit your changes (git commit -am 'Add new feature')
6. Push to the branch (git push origin feature/new-feature)
7. Create a Pull Request

Available as open source under the MIT License.

Maintained by Sashité — promoting chess variants and sharing the beauty of board game cultures.