uk.ac.bbk.dcs.automed.qproc.functions.string
Class Substring

java.lang.Object
  uk.ac.bbk.dcs.automed.qproc.functions.string.Substring

All Implemented Interfaces:

BuiltInFunction

public class Substring
extends java.lang.Object
implements BuiltInFunction

Returns a substring of the input string based on the two other integer arguments.

The substring includes the letter denoted by the first integer argument, but does not inlude the letter denoted by the second integer argument. For example 'Substring 'string' 2 4' returns 'tr'.

Author:

Lucas Zamboulis

Constructor Summary

Substring()

Method Summary

int	getArity() Returns the arity of the function.
Cell	perform(Cell[] args, Evaluator e) Returns a Cell object that is the root of a graph that represents the result of applying the built-in function to the arguments args.

Methods inherited from class java.lang.Object

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

Constructor Detail

Substring

public Substring()

Method Detail

getArity

public int getArity()

Description copied from interface: BuiltInFunction

Returns the arity of the function.

Specified by:

getArity in interface BuiltInFunction

perform

public Cell perform(Cell[] args,
                    Evaluator e)

Description copied from interface: BuiltInFunction

Returns a Cell object that is the root of a graph that represents the result of applying the built-in function to the arguments args. Uses the Evaluator e to evaluate any sub-queries that need to be evaluated.

Specified by:

perform in interface BuiltInFunction