Class: Babelfish::Phrase::Compiler

Inherits:
Object
  • Object
show all
Defined in:
lib/babelfish/phrase/compiler.rb

Overview

Babelfish AST Compiler. Compiles AST to string or to Proc.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(ast = nil) ⇒ Compiler

Returns a new instance of Compiler.



13
14
15
 
# File 'lib/babelfish/phrase/compiler.rb', line 13

def initialize( ast = nil )
    init( ast )  unless ast.nil?
end

Instance Attribute Details

#ast ⇒ Object

Returns the value of attribute ast.



11
12
13
 
# File 'lib/babelfish/phrase/compiler.rb', line 11

def ast
  @ast
end

Instance Method Details

#compile(ast) ⇒ Object

Result is string when possible; Proc otherwise.



30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
 
# File 'lib/babelfish/phrase/compiler.rb', line 30

def compile ( ast )
    init( ast )  unless ast.nil?

    throw("No AST given")  if ast.nil?
    throw("Empty AST given")  if ast.length == 0;

    if ast.length == 1 && ast.first.kind_of?(Babelfish::Phrase::Literal)
        #  просто строка
        return ast.first.text
    end

    ready = ast.map do |node|
        case node
        when Babelfish::Phrase::Literal
            node.text
        when Babelfish::Phrase::Variable
            node
        when Babelfish::Phrase::PluralForms
            sub = node.to_ruby_method
        else
            throw("Unknown AST node: #{node}")
        end
    end

    lambda do |params|
        data = ready.map do |what|
            case what
            when Babelfish::Phrase::Variable
                params[what.name.to_s].to_s
            when Proc
                what = what.call(params)
            else
                what
            end
        end.join('')
        data
    end
end

#init(ast) ⇒ Object

Initializes compiler. Should not be called directly.



18
19
20
 
# File 'lib/babelfish/phrase/compiler.rb', line 18

def init( ast )
    self.ast = ast
end

#throw(message) ⇒ Object

Throws given message in compiler context.



23
24
25
 
# File 'lib/babelfish/phrase/compiler.rb', line 23

def throw( message )
    raise "Cannot compile: #{message}";
end