Module com.darkcollective.relix.ast
Package com.darkcollective.relix.ast

Record Class NullOperand

java.lang.Object
java.lang.Record
com.darkcollective.relix.ast.NullOperand
Record Components:
location - the source location of this operand; never null
All Implemented Interfaces:
Operand
public record NullOperand(SourceLocation location) extends Record implements Operand
The NULL literal (NULL or ⊥) written as a value: the missing value itself, as in IIf(late, NULL, fee) or COUNT(IIf(ok, id, NULL)).

It has no type of its own. Analysis gives it the type its context expects — the other branch of a conditional, the column it is compared with — and ANY where nothing does. In a null test, x = NULL and x IS NULL, the word is not this operand: those parse to a NullPredicate.

  • Constructor Details

    • NullOperand

      public NullOperand(SourceLocation location)
      Creates an instance of a NullOperand record class.
      Parameters:
      location - the value for the location record component

    • NullOperand

      public NullOperand()
      Convenience constructor for tests; uses SourceLocation.UNKNOWN.

  • Method Details

    • accept

      public <R> R accept(OperandVisitor<R> visitor)
      Specified by:
      accept in interface Operand

    • toString

      public final String toString()
      Returns a string representation of this record class. The representation contains the name of the class, followed by the name and value of each of the record components.
      Specified by:
      toString in class Record
      Returns:
      a string representation of this object

    • hashCode

      public final int hashCode()
      Returns a hash code value for this object. The value is derived from the hash code of each of the record components.
      Specified by:
      hashCode in class Record
      Returns:
      a hash code value for this object

    • equals

      public final boolean equals(Object o)
      Indicates whether some other object is "equal to" this one. The objects are equal if the other object is of the same class and if all the record components are equal. All components in this record class are compared with Objects::equals(Object,Object).
      Specified by:
      equals in class Record
      Parameters:
      o - the object with which to compare
      Returns:
      true if this object is the same as the o argument; false otherwise.

    • location

      public SourceLocation location()
      Returns the value of the location record component.
      Specified by:
      location in interface Operand
      Returns:
      the value of the location record component