add Block#then: & Block#after:

lib/block.fy

@@ -246,4 +246,32 @@ class Block {
 
     iterations times: self
   }
+
+  def then: block {
+    """
+    @block @Block@ to call after @self.
+    @return @Block@ that calls @self, then @block.
+
+    Example:
+          # prints \"Hello World!\"
+          { \"Hello\" print } then: { \"World!\" println }
+    """
+
+    { self call; block call }
+  }
+
+  alias_method: 'before: for: 'then:
+
+  def after: block {
+    """
+    @block @Block@ to call before @self.
+    @return @Block@ that calls @self after calling @block.
+
+    Example:
+          # prints \"Hello World!\"
+          { \"World!\" println } after: { \"Hello\" print }
+    """
+
+    { block call; self call }
+  }
 }

tests/block.fy

@@ -322,4 +322,22 @@ FancySpec describe: Block with: {
                 ['city, "San Francisco"],
                 'male, 'programmer, 'happy]
   }
+
+  it: "returns a Block that calls self then a given Block" with: 'then: when: {
+    a = []
+    block = { a << 1 } then: { a << 2 }
+    block call
+    a is: [1,2]
+    block call
+    a is: [1,2,1,2]
+  }
+
+  it: "returns a Block that calls itself after a given Block" with: 'after: when: {
+    a = []
+    block = { a << 1 } after: { a << 2}
+    block call
+    a is: [2,1]
+    block call
+    a is: [2,1,2,1]
+  }
 }