Package it.unive.lisa.symbolic.value.operator.ternary

Class StringSubstring

  • All Implemented Interfaces:
    Operator, StringOperator, TernaryOperator
    public class StringSubstring
extends java.lang.Object
implements StringOperator, TernaryOperator
    Given three expressions, with the first one evaluating to a string value and the second and third one evaluating to integral numerical values, a TernaryExpression using this operator computes a new string corresponding to the portion of first argument's string starting at the second argument's number position (inclusive) and ending at the third argument's number position (exclusive).
    Note that:
    • both second and third argument's numbers must be non-negative and less than the length of the first argument's string, with the second one's less or equal than the third one's
    • if the second and third argument's numbers are equal, the empty string is returned

    First argument expression type: StringType
    Second argument expression type: NumericType
    Third argument expression type: NumericType
    Computed expression type: StringType

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static StringSubstring INSTANCE
      The singleton instance of this class.

    • Constructor Summary

      Constructors 
      Modifier Constructor Description
      protected StringSubstring()
      Builds the operator.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      java.lang.String toString()  
      java.util.Set<Type> typeInference​(TypeSystem types, java.util.Set<Type> left, java.util.Set<Type> middle, java.util.Set<Type> right)
      Computes the runtime types of this expression (i.e., of the result of this expression) assuming that the arguments of this expression have the given types.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

    • Field Detail

      • INSTANCE

        public static final StringSubstring INSTANCE
        The singleton instance of this class.

    • Constructor Detail

      • StringSubstring

        protected StringSubstring()
        Builds the operator. This constructor is visible to allow subclassing: instances of this class should be unique, and the singleton can be retrieved through field INSTANCE.

    • Method Detail

      • toString

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

      • typeInference

        public java.util.Set<Type> typeInference​(TypeSystem types,
                                         java.util.Set<Type> left,
                                         java.util.Set<Type> middle,
                                         java.util.Set<Type> right)
        Description copied from interface: TernaryOperator
        Computes the runtime types of this expression (i.e., of the result of this expression) assuming that the arguments of this expression have the given types.
        Specified by:
        typeInference in interface TernaryOperator
        Parameters:
        types - the type system knowing about the types of the current program
        left - the set of types of the left-most argument of this expression
        middle - the set of types of the middle argument of this expression
        right - the set of types of the right-most argument of this expression
        Returns:
        the runtime types of this expression