Class: Faust2Ruby::Parser

Inherits:
Object
  • Object
show all
Defined in:
lib/faust2ruby/parser.rb

Overview

Recursive descent parser for Faust DSP programs. Grammar based on Faust’s official grammar with simplified precedence.

Defined Under Namespace

Classes: ParseError

Constant Summary collapse

PRECEDENCE =

Operator precedence (lowest to highest) In Faust: SEQ < PAR < SPLIT/MERGE < REC < arithmetic

{
  PAR: 1,      # , (parallel - lowest, used as arg separator)
  SEQ: 2,      # : (sequential)
  SPLIT: 3,    # <:
  MERGE: 3,    # :>
  REC: 4,      # ~
  OR: 5,       # |
  AND: 6,      # &
  LT: 7, GT: 7, LE: 7, GE: 7, EQ: 7, NEQ: 7,  # comparison
  ADD: 8, SUB: 8,  # + -
  MUL: 9, DIV: 9, MOD: 9,  # * / %
  POW: 10,     # ^
  DELAY: 11,   # @
}.freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(source) ⇒ Parser

Returns a new instance of Parser.



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# File 'lib/faust2ruby/parser.rb', line 37

def initialize(source)
  @lexer = Lexer.new(source)
  @tokens = @lexer.tokenize
  @pos = 0
  @errors = @lexer.errors.dup
end

Instance Attribute Details

#errors ⇒ Object (readonly)

Returns the value of attribute errors.



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# File 'lib/faust2ruby/parser.rb', line 53

def errors
  @errors
end

Instance Method Details

#parse ⇒ Object 



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# File 'lib/faust2ruby/parser.rb', line 44

def parse
  statements = []
  until current_type == :EOF
    stmt = parse_statement
    statements << stmt if stmt
  end
  AST::Program.new(statements)
end