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Task/Singly-linked-list-Element-insertion/Oforth/singly-linked-list-element-insertion.oforth

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+Collection Class new: LinkedList(data, mutable next)
+
+LinkedList method: initialize   := next := data ;
+LinkedList method: data   @data ;
+LinkedList method: next   @next ;
+LinkedList method: add(e) e @next LinkedList new := next ;
+
+LinkedList method: forEachNext
+   dup ifNull: [ drop self ]
+   dup 1 ifEq: [ drop false return ]
+   dup next dup ifNull: [ drop 1 ]
+   swap data true ;
+
+: testLink  LinkedList new($A, null) dup add($B) dup add($C) ;
+
+testLink println