Class: Heist::RubyParser

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

Overview

RubyParser parses non-string code given as Ruby data such as arrays. It allows Lisp-style code to be expressed inline with Ruby, for example:

scheme = Heist::Runtime.new
scheme.exec [:define, [:square, :x], [:*, :x, :x]]
scheme.exec [:square, 9]
#=> 81

The above API uses RubyParser behind the scenes to turn Ruby data into Heist runtime objects such as Cons based lists before execution.

Constant Summary collapse

DOT = 
:'.'

Instance Method Summary collapse

Instance Method Details

#parse(source) ⇒ Object

Parses a single piece of Ruby data in



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# File 'lib/heist/parser/ruby.rb', line 18

def parse(source)
  case source
    when Array then
      members, tail = *(source[-2] == DOT ? [source[0..-3], source.last] : [source, nil])
      list = Runtime::Cons.construct(members) { |cell| parse(cell) }
      list.tail.cdr = parse(tail) if tail
      list
    when Symbol then
      Runtime::Identifier.new(source)
    else
      source
  end
end