split out parsers into separate files

11 files changed, 141 insertions, 121 deletions

diff --git a/lib/mpeg.rb b/lib/mpeg.rb
index d4ae8f9..c53cf89 100644
--- a/lib/mpeg.rb
+++ b/lib/mpeg.rb
@@ -1,5 +1,16 @@
-require "mpeg/parser"
 require "mpeg/version"
+require "mpeg/base"
+
+require "mpeg/alternative"
+require "mpeg/input"
+require "mpeg/lookahead"
+require "mpeg/parser"
+require "mpeg/parser"
+require "mpeg/re"
+require "mpeg/repitition"
+require "mpeg/sequence"
+require "mpeg/slice"
+require "mpeg/str"
 
 module Mpeg
   class Error < StandardError; end
diff --git a/lib/mpeg/alternative.rb b/lib/mpeg/alternative.rb
new file mode 100644
index 0000000..148b265
--- /dev/null
+++ b/lib/mpeg/alternative.rb
@@ -0,0 +1,12 @@
+module Mpeg
+  class Alternative < Base
+    def initialize(left, right)
+      @left = left
+      @right = right
+    end
+
+    def call(input)
+      @left.call(input) || @right.call(input)
+    end
+  end
+end
diff --git a/lib/mpeg/base.rb b/lib/mpeg/base.rb
new file mode 100644
index 0000000..33c7e6a
--- /dev/null
+++ b/lib/mpeg/base.rb
@@ -0,0 +1,23 @@
+module Mpeg
+  class Base
+    def parse(string)
+      call(Input.new(string))
+    end
+
+    def repeat(min = 0, max = nil)
+      Repitition.new(self, min, max)
+    end
+
+    def |(parser)
+      Alternative.new(self, parser)
+    end
+
+    def >>(parser)
+      Sequence.new(self, parser)
+    end
+
+    def absent?
+      Lookahead.new(self, false)
+    end
+  end
+end
diff --git a/lib/mpeg/input.rb b/lib/mpeg/input.rb
new file mode 100644
index 0000000..03ef6d7
--- /dev/null
+++ b/lib/mpeg/input.rb
@@ -0,0 +1,18 @@
+module Mpeg
+  class Input
+    def initialize(string)
+      @scanner = StringScanner.new(string)
+    end
+
+    def matches?(pattern)
+      @scanner.match?(pattern)
+    end
+
+    def consume(characters)
+      position = @scanner.pos
+      slice = @scanner.scan(/(.|$){#{characters}}/m)
+
+      Slice.new(position, slice)
+    end
+  end
+end
diff --git a/lib/mpeg/lookahead.rb b/lib/mpeg/lookahead.rb
new file mode 100644
index 0000000..7fcbf3d
--- /dev/null
+++ b/lib/mpeg/lookahead.rb
@@ -0,0 +1,8 @@
+module Mpeg
+  class Lookahead < Base
+    def initialize(parser, positive)
+      @parser = parser
+      @positive = positive
+    end
+  end
+end
diff --git a/lib/mpeg/parser.rb b/lib/mpeg/parser.rb
index 1a313d4..9295fcf 100644
--- a/lib/mpeg/parser.rb
+++ b/lib/mpeg/parser.rb
@@ -1,124 +1,4 @@
 module Mpeg
-  class Base
-    def parse(string)
-      call(Input.new(string))
-    end
-
-    def repeat(min = 0, max = nil)
-      Repitition.new(self, min, max)
-    end
-
-    def |(parser)
-      Alternative.new(self, parser)
-    end
-
-    def >>(parser)
-      Sequence.new(self, parser)
-    end
-
-    def absent?
-      Lookahead.new(self, false)
-    end
-  end
-
-  class Slice
-    def initialize(position, string)
-    end
-  end
-
-  class Input
-    def initialize(string)
-      @scanner = StringScanner.new(string)
-    end
-
-    def matches?(pattern)
-      @scanner.match?(pattern)
-    end
-
-    def consume(characters)
-      position = @scanner.pos
-      slice = @scanner.scan(/(.|$){#{characters}}/m)
-
-      Slice.new(position, slice)
-    end
-  end
-
-  class Lookahead < Base
-    def initialize(parser, positive)
-      @parser = parser
-      @positive = positive
-    end
-  end
-
-  class Sequence < Base
-    def initialize(left, right)
-      @left = left
-      @right = right
-    end
-
-    def call(input)
-      @left.call(input) && @right.call(input)
-    end
-  end
-
-  class Alternative < Base
-    def initialize(left, right)
-      @left = left
-      @right = right
-    end
-
-    def call(input)
-      @left.call(input) || @right.call(input)
-    end
-  end
-
-  class Repitition < Base
-    def initialize(parser, min, max)
-      @parser = parser
-      @min = min
-      @max = max
-    end
-
-    def call(input)
-      occurrences = 0
-      loop do
-        break unless @parser.call(input)
-        occurrences += 1
-        return false if @max && occurrences > @max
-      end
-      occurrences >= @min
-    end
-  end
-
-  class Re < Base
-    def initialize(regex)
-      @regex = Regexp.new("[#{regex}]", Regexp::MULTILINE)
-    end
-
-    def call(input)
-      if input.matches?(@regex)
-        input.consume(1)
-        return true
-      end
-      false
-    end
-  end
-
-  class Str < Base
-    def initialize(string)
-      @length = string.size
-      @regex = Regexp.new(Regexp.escape(string))
-    end
-
-    def call(input)
-      if input.matches?(@regex)
-        input.consume(1)
-        return true
-      end
-      false
-    end
-  end
-
   class Parser
     def parse(string)
       root.parse(string)
diff --git a/lib/mpeg/re.rb b/lib/mpeg/re.rb
new file mode 100644
index 0000000..61df57c
--- /dev/null
+++ b/lib/mpeg/re.rb
@@ -0,0 +1,15 @@
+module Mpeg
+  class Re < Base
+    def initialize(regex)
+      @regex = Regexp.new("[#{regex}]", Regexp::MULTILINE)
+    end
+
+    def call(input)
+      if input.matches?(@regex)
+        input.consume(1)
+        return true
+      end
+      false
+    end
+  end
+end
diff --git a/lib/mpeg/repitition.rb b/lib/mpeg/repitition.rb
new file mode 100644
index 0000000..9903b60
--- /dev/null
+++ b/lib/mpeg/repitition.rb
@@ -0,0 +1,19 @@
+module Mpeg
+  class Repitition < Base
+    def initialize(parser, min, max)
+      @parser = parser
+      @min = min
+      @max = max
+    end
+
+    def call(input)
+      occurrences = 0
+      loop do
+        break unless @parser.call(input)
+        occurrences += 1
+        return false if @max && occurrences > @max
+      end
+      occurrences >= @min
+    end
+  end
+end
diff --git a/lib/mpeg/sequence.rb b/lib/mpeg/sequence.rb
new file mode 100644
index 0000000..e3823de
--- /dev/null
+++ b/lib/mpeg/sequence.rb
@@ -0,0 +1,12 @@
+module Mpeg
+  class Sequence < Base
+    def initialize(left, right)
+      @left = left
+      @right = right
+    end
+
+    def call(input)
+      @left.call(input) && @right.call(input)
+    end
+  end
+end
diff --git a/lib/mpeg/slice.rb b/lib/mpeg/slice.rb
new file mode 100644
index 0000000..cb6c7aa
--- /dev/null
+++ b/lib/mpeg/slice.rb
@@ -0,0 +1,6 @@
+module Mpeg
+  class Slice
+    def initialize(position, string)
+    end
+  end
+end
diff --git a/lib/mpeg/str.rb b/lib/mpeg/str.rb
new file mode 100644
index 0000000..f5266e9
--- /dev/null
+++ b/lib/mpeg/str.rb
@@ -0,0 +1,16 @@
+module Mpeg
+  class Str < Base
+    def initialize(string)
+      @length = string.size
+      @regex = Regexp.new(Regexp.escape(string))
+    end
+
+    def call(input)
+      if input.matches?(@regex)
+        input.consume(1)
+        return true
+      end
+      false
+    end
+  end
+end