Class: Sangi::Parser

Inherits:
Object
  • Object
show all
Defined in:
lib/sangi/parser.rb

Constant Summary collapse

PATTERN = 
/\A\s*([+-]?\d+)\s*([+-])\s*([+-]?\d+)\s*\z/

Instance Method Summary collapse

Constructor Details

#initialize(config) ⇒ Parser

Returns a new instance of Parser.



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# File 'lib/sangi/parser.rb', line 5

def initialize(config)
  @config = config
end

Instance Method Details

#parse(source) ⇒ Object

Raises:



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# File 'lib/sangi/parser.rb', line 9

def parse(source)
  match = PATTERN.match(source.to_s)
  raise ParseError, parse_error_message unless match

  operator_text = match[2]
  right_text = match[3]
  raise ParseError, parse_error_message if operator_text == "+" && right_text.start_with?("+")

  left = normalize_zero(match[1].to_i)
  operator = operator_text.to_sym
  right = normalize_zero(right_text.to_i)

  validate_digits!(left)
  validate_digits!(right)

  Expression.new(
    left: left,
    operator: operator,
    right: right,
    source: source.to_s
  )
end