Package net.hydromatic.morel.eval

Class Unit

  • All Implemented Interfaces:
    java.lang.Comparable<Unit>, java.lang.Iterable, java.util.Collection, java.util.List
    public class Unit
extends java.util.AbstractList
implements java.lang.Comparable<Unit>
    A placeholder value for the "unit" type.

    We sometimes use it as a dummy value when we need to add a variable (and its type) to the compilation environment but we don't have a value (because it's not a runtime environment).

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static Unit INSTANCE  

      • Fields inherited from class java.util.AbstractList

        modCount

    • Constructor Summary

      Constructors 
      Modifier Constructor Description
      private Unit()  

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      int compareTo​(Unit o)  
      java.lang.Object get​(int index)  
      int size()  
      java.lang.String toString()  

      • Methods inherited from class java.util.AbstractList

        add, add, addAll, clear, equals, hashCode, indexOf, iterator, lastIndexOf, listIterator, listIterator, remove, removeRange, set, subList

      • Methods inherited from class java.util.AbstractCollection

        addAll, contains, containsAll, isEmpty, remove, removeAll, retainAll, toArray, toArray

      • Methods inherited from class java.lang.Object

        clone, finalize, getClass, notify, notifyAll, wait, wait, wait

      • Methods inherited from interface java.util.Collection

        parallelStream, removeIf, stream, toArray

      • Methods inherited from interface java.lang.Iterable

        forEach

      • Methods inherited from interface java.util.List

        addAll, contains, containsAll, isEmpty, remove, removeAll, replaceAll, retainAll, sort, spliterator, toArray, toArray

    • Field Detail

      • INSTANCE

        public static final Unit INSTANCE

    • Constructor Detail

      • Unit

        private Unit()

    • Method Detail

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.util.AbstractCollection

      • get

        public java.lang.Object get​(int index)
        Specified by:
        get in interface java.util.List
        Specified by:
        get in class java.util.AbstractList

      • size

        public int size()
        Specified by:
        size in interface java.util.Collection
        Specified by:
        size in interface java.util.List
        Specified by:
        size in class java.util.AbstractCollection

      • compareTo

        public int compareTo​(Unit o)
        Specified by:
        compareTo in interface java.lang.Comparable<Unit>