1 files changed, 19 insertions, 8 deletions
diff --git a/src/guff/template.cr b/src/guff/template.cr
index 4b54fb6..f5a1693 100644
--- a/src/guff/template.cr
+++ b/src/guff/template.cr
@@ -7,16 +7,19 @@ module Guff
       @has_keys = @tokens.select { |t| t.type == :key }.size > 0
     end
 
-    def run(args = nil : Hash(String, String)?) : String
+    def run(args : Nil) : String
+      raise_missing if @has_keys
+
+      # return literal string
+      @string
+    end
+
+    def run(
+      args = {} of String => String : Hash(String, String)
+    ) : String
       if @has_keys
         # check template args
-        if !args || args.size == 0
-          raise "missing template args: %s" % [@tokens.select { |t|
-            t.type == :key
-          }.map { |t|
-            t.value
-          }.sort.join(", ")]
-        end
+        raise_missing if args.size == 0
 
         # build result
         String.build do |r|
@@ -30,6 +33,14 @@ module Guff
       end
     end
 
+    private def raise_missing
+      raise "missing template args: %s" % [@tokens.select { |t|
+        t.type == :key
+      }.map { |t|
+        t.value
+      }.sort.join(", ")]
+    end
+
     SCAN_RE = %r{
       # match key
       (?:%\{(?<key>[^\}]+)\})