propane/lib/propane/generator.rb

59 lines
1.7 KiB
Ruby

class Propane
class Generator
def initialize(grammar, output_file, log_file)
@grammar = grammar
@output_file = output_file
@log_file = log_file
@classname = @grammar.classname || File.basename(output_file).sub(%r{[^a-zA-Z0-9].*}, "").capitalize
process_grammar!
@lexer = Lexer.new(@grammar.tokens, @grammar.drop_tokens)
@parser = Parser.new(@grammar.rule_sets)
end
def generate
erb = ERB.new(File.read(File.join(File.dirname(File.expand_path(__FILE__)), "../../assets/parser.d.erb")), trim_mode: "<>")
result = erb.result(binding.clone)
File.open(@output_file, "wb") do |fh|
fh.write(result)
end
end
private
def process_grammar!
tokens_by_name = {}
@grammar.tokens.each do |token|
if tokens_by_name.include?(token.name)
raise Error.new("Duplicate token name #{token.name.inspect}")
end
tokens_by_name[token.name] = token
end
@grammar.rule_sets.each do |rule_name, rule_set|
if tokens_by_name.include?(rule_name)
raise Error.new("Rule name collides with token name #{rule_name.inspect}")
end
end
unless @grammar.rule_sets["Start"]
raise Error.new("Start rule not found")
end
@grammar.rule_sets.each do |rule_name, rule_set|
rule_set.rules.each do |rule|
rule.components.map! do |component|
if tokens_by_name[component]
tokens_by_name[component]
elsif @grammar.rule_sets[component]
@grammar.rule_sets[component]
else
raise Error.new("Symbol #{component} not found")
end
end
end
end
end
end
end