org.rigwit

Class Forth

java.lang.Object

org.rigwit.Forth

public class Forth
extends java.lang.Object

A Forth interpreter class. It is an ITC based Forth compiler with the primitives written in Java. It uses a 32-bit (aligned) cell with a 16-bit character.

Constructor Summary

Constructors

Constructor and Description
Forth() Initialise the Forth virtual machine.

Method Summary

Methods

Modifier and Type	Method and Description
void	addArgument(java.lang.String arg) Add a string to the list of command line arguments passed into the Forth application.
void	interpret() Interpret text from the standard terminal device, using the ForthTerminalReader.
void	interpret(java.io.File file) Interpret the file as Forth source code.
void	interpret(java.lang.String text) Interpret a string of text as forth source code.
void	interpret(java.lang.String text, java.lang.String source) Interpret a string of text as forth source code from a named source.
void	interpretFile(java.lang.String filename) Interpret the given file as Forth source code.
void	setDataStackCells(int size) Set the maximum number of cells the data data should be able to hold.
void	setReturnStackCells(int size) Set the maximum number of cells the return data should be able to hold.

Methods inherited from class java.lang.Object

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

Constructor Detail

Forth

public Forth()

Initialise the Forth virtual machine. Loads the core wordset.

Method Detail

interpret

public void interpret()
               throws java.io.IOException

Interpret text from the standard terminal device, using the ForthTerminalReader.

Enter the standard forth text interpreter. This will display the ok prompt and await the user input, interpreting it one line at a time. Errors in the text input are processed by the interpreter.

Stops the loop and returns when the user executes the BYE word.

Throws:

java.io.IOException - if there is a problem reading the terminal.

interpret

public void interpret(java.io.File file)
               throws java.io.FileNotFoundException,
                      java.io.IOException

Interpret the file as Forth source code. Interpret the file as forth source code, one line at a time.

Parameters:

file - The File object to be interpreted.

Throws:

java.io.FileNotFoundException - When the source file (file) could not be opened.

java.io.IOException - When there is a problem reading the file.

interpret

public void interpret(java.lang.String text)
               throws java.io.IOException

Interpret a string of text as forth source code. Note that the string is not evaluated, but is interpreted as if the text came from the keyboard. If there is a problem with the text a ForthException is thrown with the calling method being identified as the source of the text.

Parameters:

text - The string of source code to be interpreted.

Throws:

java.io.IOException - if there is a problem reading the string.

interpret

public void interpret(java.lang.String text,
             java.lang.String source)
               throws java.io.IOException

Interpret a string of text as forth source code from a named source. Should there be an error in the text the source name is used to identify the source of the error. Note that the string is not evaluated, but is interpreted as if the text came from the keyboard.

Parameters:

text - The string of Forth source to be interpreted.

source - The name of the source input (for error reporting).

Throws:

java.io.IOException - if there is a problem reading the string.

interpretFile

public void interpretFile(java.lang.String filename)
                   throws ForthException,
                          java.io.FileNotFoundException,
                          java.io.IOException

Interpret the given file as Forth source code. Look for the file file with the default extension.

Parameters:

filename - The name of the file to be interpreted.

Throws:

ForthException - may be thrown by the force code

java.io.FileNotFoundException - when the file (filename) could not be located

java.io.IOException - if there is a difficulty reading the file.

setDataStackCells

public void setDataStackCells(int size)

Set the maximum number of cells the data data should be able to hold. The default size is 2048 cells. This may only be invoked before before any text is interpreted.

Parameters:

size - the maximum number of cells the data data should be able to hold.

setReturnStackCells

public void setReturnStackCells(int size)

Set the maximum number of cells the return data should be able to hold. The default size is 2048 cells. The data size must be set prior to interpreting any text.

Parameters:

size - the maximum number of cells the return data should be able to hold.

addArgument

public void addArgument(java.lang.String arg)

Add a string to the list of command line arguments passed into the Forth application.

Parameters:

arg - a string argument.