class Calyx::Syntax::Unique

A type of production rule representing a unique substitution which only returns values that have not previously been selected. The probability that a given rule will be selected increases as more selections are made and the list grows smaller.

Constants

SIGIL

Public Class Methods

new(symbol, registry) click to toggle source

Construct a unique rule, given the symbol to lookup and the registry to look it up in.

@param [Symbol] symbol @param [Calyx::Registry] registry

# File lib/calyx/syntax/unique.rb, line 15
def initialize(symbol, registry)
  @symbol = symbol.slice(1, symbol.length-1).to_sym
  @registry = registry
end

Public Instance Methods

evaluate(options) click to toggle source

Evaluate the unique rule, using the registry to handle the expansion and keep track of previous selections.

@param [Calyx::Options] options @return [Array]

# File lib/calyx/syntax/unique.rb, line 25
def evaluate(options)
  [@symbol, @registry.unique_expansion(@symbol)]
end