Change to NigelThorne fork to detect infinite loops

and fixed grammar to ignore missing parameter list.

Gemfile

@@ -1,8 +1,11 @@
 source "http://rubygems.org"
 
-gem "parslet" , "~> 1.6.1"
+gem "parslet" , :git => 'https://github.com/NigelThorne/parslet.git'
 
 group :development do
   gem "minitest"
   gem "simplecov"
+  gem "jeweler"
+  gem "roodi"
+  gem 'pry'
 end

Gemfile.lock

@@ -1,22 +1,89 @@
+GIT
+  remote: https://github.com/NigelThorne/parslet.git
+  revision: be698466bfa21a35d838fc7d3cd741b8aa1977b0
+  specs:
+    parslet (1.7.0)
+      blankslate (~> 2.0)
+
 GEM
   remote: http://rubygems.org/
   specs:
+    addressable (2.3.6)
     blankslate (2.1.2.4)
+    builder (3.2.2)
+    coderay (1.1.0)
+    descendants_tracker (0.0.4)
+      thread_safe (~> 0.3, >= 0.3.1)
     docile (1.1.3)
+    faraday (0.9.0)
+      multipart-post (>= 1.2, < 3)
+    git (1.2.6)
+    github_api (0.11.3)
+      addressable (~> 2.3)
+      descendants_tracker (~> 0.0.1)
+      faraday (~> 0.8, < 0.10)
+      hashie (>= 1.2)
+      multi_json (>= 1.7.5, < 2.0)
+      nokogiri (~> 1.6.0)
+      oauth2
+    hashie (2.1.1)
+    highline (1.6.21)
+    jeweler (2.0.1)
+      builder
+      bundler (>= 1.0)
+      git (>= 1.2.5)
+      github_api
+      highline (>= 1.6.15)
+      nokogiri (>= 1.5.10)
+      rake
+      rdoc
+    json (1.8.1)
+    jwt (1.0.0)
+    method_source (0.8.2)
+    mini_portile (0.6.0)
     minitest (5.3.2)
     multi_json (1.9.2)
-    parslet (1.6.1)
+    multi_xml (0.5.5)
-      blankslate (~> 2.0)
+    multipart-post (2.0.0)
+    nokogiri (1.6.2.1)
+      mini_portile (= 0.6.0)
+    nokogiri (1.6.2.1-x64-mingw32)
+      mini_portile (= 0.6.0)
+    oauth2 (0.9.4)
+      faraday (>= 0.8, < 0.10)
+      jwt (~> 1.0)
+      multi_json (~> 1.3)
+      multi_xml (~> 0.5)
+      rack (~> 1.2)
+    pry (0.9.12.6)
+      coderay (~> 1.0)
+      method_source (~> 0.8)
+      slop (~> 3.4)
+    rack (1.5.2)
+    rake (10.3.2)
+    rdoc (4.1.1)
+      json (~> 1.4)
+    roodi (4.0.0)
+      ruby_parser (~> 3.2, >= 3.2.2)
+    ruby_parser (3.6.1)
+      sexp_processor (~> 4.1)
+    sexp_processor (4.4.3)
     simplecov (0.8.2)
       docile (~> 1.1.0)
       multi_json
       simplecov-html (~> 0.8.0)
     simplecov-html (0.8.0)
+    slop (3.5.0)
+    thread_safe (0.3.4)
 
 PLATFORMS
   ruby
+  x64-mingw32
 
 DEPENDENCIES
+  jeweler
   minitest
-  parslet (~> 1.6.1)
+  parslet!
+  pry
+  roodi
   simplecov

lib/parser/crystal.rb

@@ -31,6 +31,7 @@ module Parser
     include Operators
     include ModuleDef
 
-    rule(:root){ (module_definition | class_definition | function_definition | expression  | call_site ).repeat }
+    rule(:root_body)    {(module_definition | class_definition | function_definition | expression  | call_site )}
+    rule(:root)         { root_body.repeat() }
   end
 end

lib/parser/function_definition.rb

@@ -4,7 +4,7 @@ module Parser
     
     rule(:function_definition) {
       keyword_def >> ((module_name|instance_variable|name).as(:receiver) >> str(".")).maybe >> #possibly qualified
-                  name.as(:function_name) >> parmeter_list >> newline >> expressions_end >> newline
+                  name.as(:function_name) >> parmeter_list.maybe >> newline >> expressions_end >> newline
     }
 
     rule(:parmeter_list) {

lib/parser/module_definition.rb

@@ -3,12 +3,12 @@ module Parser
     include Parslet
     rule(:module_definition) do
       keyword_module >> module_name >> eol >>
-      ( (keyword_end.absent? >> root).repeat(1)).as(:module_expressions) >> keyword_end >> newline
+      ( (keyword_end.absent? >> root_body).repeat()).as(:module_expressions) >> keyword_end >> newline
     end
 
     rule(:class_definition) do
       keyword_class >> module_name >> eol >>
-      ( (keyword_end.absent? >> root).repeat(1)).as(:class_expressions) >> keyword_end >> newline
+      ( (keyword_end.absent? >> root_body).repeat()).as(:class_expressions) >> keyword_end >> newline
     end
 
   end