Template::Seq -> Sequence

Author: HertzDevil

spec/bindgen/template_spec.cr

@@ -26,7 +26,7 @@ describe "Template" do
     it "returns false for any other templates" do
       conversion1 = Bindgen::Template::Basic.new("%x")
       conversion2 = Bindgen::Template::Basic.new("%x", simple: true)
-      conversion3 = Bindgen::Template::Seq.new(conversion1, conversion2)
+      conversion3 = Bindgen::Template::Sequence.new(conversion1, conversion2)
 
       conversion1.no_op?.should be_false
       conversion2.no_op?.should be_false
@@ -38,7 +38,7 @@ describe "Template" do
     it "composes two templates" do
       conversion1 = Bindgen::Template::Basic.new("%x")
       conversion2 = Bindgen::Template::Basic.new("%y")
-      conversion3 = Bindgen::Template::Seq.new(conversion1, conversion2)
+      conversion3 = Bindgen::Template::Sequence.new(conversion1, conversion2)
 
       conversion1.followed_by(conversion2).should eq(conversion3)
     end
@@ -75,12 +75,16 @@ describe "Template" do
     end
   end
 
-  describe "Seq#template" do
-    it "composes two templates" do
-      first = Bindgen::Template::Basic.new("%_a")
-      second = Bindgen::Template::Basic.new("%_b")
-      conversion = Bindgen::Template::Seq.new(first: first, second: second)
+  describe "Sequence#template" do
+    it "composes multiple templates" do
+      a_conv = Bindgen::Template::Basic.new("%_a")
+      b_conv = Bindgen::Template::Basic.new("%_b")
+
+      conversion = Bindgen::Template::Sequence.new(a_conv, b_conv)
       conversion.template("c").should eq("c_a_b")
+
+      conversion = Bindgen::Template::Sequence.new(a_conv, a_conv, a_conv, b_conv, b_conv, a_conv)
+      conversion.template("c").should eq("c_a_a_a_b_b_a")
     end
   end
 end

src/bindgen/template.cr

@@ -28,7 +28,7 @@ module Bindgen
       def followed_by(other : Base) : Base
         return other if no_op?
         return self if other.no_op?
-        Seq.new(first: self, second: other)
+        Sequence.new(self, other)
       end
     end
 
@@ -68,19 +68,31 @@ module Bindgen
       def_equals @pattern, @simple
     end
 
-    # Compound template which runs *code* through two child templaters.
-    class Seq < Base
-      @first : Base
-      @second : Base
-
-      def initialize(@first, @second)
+    # Compound template which runs *code* through multiple child templater, in
+    # the order they are given in the constructor.
+    class Sequence < Base
+      getter children = Array(Base).new
+
+      def initialize(*conversions : Base)
+        conversions.each do |conversion|
+          # Flatten `Sequence` templates automatically.
+          if conversion.is_a?(Sequence)
+            @children.concat(conversion.children)
+          else
+            @children << conversion
+          end
+        end
       end
 
       def template(code) : String
-        @second.template(@first.template(code))
+        @children.each do |conversion|
+          code = conversion.template(code)
+        end
+
+        code
       end
 
-      def_equals @first, @second
+      def_equals @children
     end
 
     # Template to transform `Proc`s for Crystal wrapper types into `Proc`