Package ptolemy.data.expr

Class ExpressionFunction

  • All Implemented Interfaces:
    Function
    public class ExpressionFunction
extends java.lang.Object
implements Function
    An implementation of a function closure that encapsulates an expression tree. Instances of this class are created during the evaluation of function closure expressions in the expression language, like "function(x:int, y:int) x+y".
    Since:
    Ptolemy II 2.1
    Version:
    $Id$
    Author:
    Steve Neuendorffer, Xiaojun Liu
    See Also:
    ASTPtRootNode
    Pt.AcceptedRating:
    Red (neuendor)
    Pt.ProposedRating:
    Yellow (neuendor)

    • Constructor Summary

      Constructors 
      Constructor Description
      ExpressionFunction​(java.util.List argumentNames, Type[] argumentTypes, ASTPtRootNode exprRoot)
      Construct a function closure that encapsulates an expression tree.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      Token apply​(Token[] arguments)
      Apply the function to the list of arguments, which are tokens.
      int getNumberOfArguments()
      Return the number of arguments of the function.
      boolean isCongruent​(Function function)
      Return true if this function is congruent to the given function.
      java.lang.String toString()
      Return a string representation of this function.

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • ExpressionFunction

        public ExpressionFunction​(java.util.List argumentNames,
                          Type[] argumentTypes,
                          ASTPtRootNode exprRoot)
        Construct a function closure that encapsulates an expression tree.
        Parameters:
        argumentNames - The names of the arguments.
        argumentTypes - The types of the arguments.
        exprRoot - The Expression tree that describes the function.

    • Method Detail

      • apply

        public Token apply​(Token[] arguments)
            throws IllegalActionException
        Apply the function to the list of arguments, which are tokens.
        Specified by:
        apply in interface Function
        Parameters:
        arguments - The list of arguments.
        Returns:
        The result of applying the function to the given arguments.
        Throws:
        IllegalActionException - If thrown during evaluating the function.

      • getNumberOfArguments

        public int getNumberOfArguments()
        Return the number of arguments of the function.
        Specified by:
        getNumberOfArguments in interface Function
        Returns:
        The number of arguments of the function.

      • isCongruent

        public boolean isCongruent​(Function function)
        Return true if this function is congruent to the given function. Classes should implement this method so that two functions are congruent under any renaming of the bound variables of the function. For simplicity, a function need only be congruent to other functions of the same class.
        Specified by:
        isCongruent in interface Function
        Parameters:
        function - The function to check congruency against.
        Returns:
        True if this function is congruent.

      • toString

        public java.lang.String toString()
        Return a string representation of this function.
        Specified by:
        toString in interface Function
        Overrides:
        toString in class java.lang.Object
        Returns:
        A string representation of this function.