gnu.expr
Class Interpreter

java.lang.Object
  |
  +--gnu.expr.Interpreter

Direct Known Subclasses:

Scheme

public abstract class Interpreter

extends java.lang.Object

Contains various language-dependent methods. Also contains "global" state about the executation environment, such as the global Environment. There can be multiple Interpreters associated with different threads, representing mutiple top-levels. (However, this functionality is incomplete.)

Field Summary

static Interpreter	defaultInterpreter
protected Environment	environ
static java.lang.Boolean	falseObject
static java.lang.String	quasiquote_sym
static java.lang.String	quote_sym
static java.lang.Boolean	trueObject
static Undefined	undefinedObject
static java.lang.String	unquote_sym
static java.lang.String	unquotesplicing_sym
static java.lang.Object	voidObject

Constructor Summary

Interpreter()

Method Summary

java.lang.Object	booleanObject(boolean b)
java.lang.Object	coerceFromObject(java.lang.Class clas, java.lang.Object obj)
java.lang.Object	coerceToObject(java.lang.Class clas, java.lang.Object obj)
void	define(java.lang.String sym, java.lang.Object p)
Environment	getEnvironment()
abstract Lexer	getLexer(InPort inp, SourceMessages messages)
abstract java.lang.String	getName()
Environment	getNewEnvironment()
abstract Type	getTypeFor(java.lang.Class clas)
boolean	hasSeparateFunctionNamespace() True if functions are in a separate anme space from variable.
boolean	isTrue(java.lang.Object value) Test if a value is considered "true" in this language.
java.lang.Object	lookup(java.lang.String name)
java.lang.Object	noValue() The value to return for a "void" result.
abstract void	print(java.lang.Object obj, OutPort out)
abstract java.lang.Object	read(InPort in)
void	setEnvironment(Environment environ)

Methods inherited from class java.lang.Object

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

Field Detail

defaultInterpreter

public static Interpreter defaultInterpreter

trueObject

public static final java.lang.Boolean trueObject

falseObject

public static final java.lang.Boolean falseObject

undefinedObject

public static final Undefined undefinedObject

voidObject

public static final java.lang.Object voidObject

quote_sym

public static final java.lang.String quote_sym

unquote_sym

public static final java.lang.String unquote_sym

unquotesplicing_sym

public static final java.lang.String unquotesplicing_sym

quasiquote_sym

public static final java.lang.String quasiquote_sym

environ

protected Environment environ

Constructor Detail

Interpreter

public Interpreter()

Method Detail

isTrue

public boolean isTrue(java.lang.Object value)

Test if a value is considered "true" in this language.

booleanObject

public java.lang.Object booleanObject(boolean b)

noValue

public java.lang.Object noValue()

The value to return for a "void" result.

hasSeparateFunctionNamespace

public boolean hasSeparateFunctionNamespace()

True if functions are in a separate anme space from variable. Is true for e.g. Common Lisp, Emacs Lisp; false for Scheme.

getEnvironment

public Environment getEnvironment()

setEnvironment

public void setEnvironment(Environment environ)

define

public void define(java.lang.String sym,
                   java.lang.Object p)

lookup

public java.lang.Object lookup(java.lang.String name)

read

public abstract java.lang.Object read(InPort in)
                               throws java.io.IOException,
                                      SyntaxException

print

public abstract void print(java.lang.Object obj,
                           OutPort out)

getNewEnvironment

public Environment getNewEnvironment()

getName

public abstract java.lang.String getName()

getLexer

public abstract Lexer getLexer(InPort inp,
                               SourceMessages messages)

getTypeFor

public abstract Type getTypeFor(java.lang.Class clas)

coerceFromObject

public java.lang.Object coerceFromObject(java.lang.Class clas,
                                         java.lang.Object obj)

coerceToObject

public java.lang.Object coerceToObject(java.lang.Class clas,
                                       java.lang.Object obj)