gnu.expr
Class Expression

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

Direct Known Subclasses:

ApplyExp, BeginExp, BlockExp, ErrorExp, ExitExp, IfExp, QuoteExp, ReferenceExp, ScopeExp, SetExp, SynchronizedExp, TryExp

public abstract class Expression

extends java.lang.Object

implements Printable

Abstract class for syntactic forms that evaluate to a value. Scheme S-expressions get re-written to these before evaluation.

Constructor Summary

Expression()

Method Summary

abstract void	compile(Compilation comp, Target target)
void	compile(Compilation comp, Type type)
void	compileNotePosition(Compilation comp, Target target) Compile, but take note of line number.
void	compileWithPosition(Compilation comp, Target target) Same as compile, but emit line number beforehard.
java.lang.Object	eval(Environment env)
int	getColumn()
java.lang.String	getFile()
int	getLine() Get the line number of (the start of) this Expression.
Type	getType() Return the Type used to represent the values of this Expression.
abstract void	print(java.io.PrintWriter ps)
void	setFile(java.lang.String filename)
void	setLine(int lineno)
void	setLine(int lineno, int colno)

Methods inherited from class java.lang.Object

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

Constructor Detail

Expression

public Expression()

Method Detail

eval

public java.lang.Object eval(Environment env)

print

public abstract void print(java.io.PrintWriter ps)

Specified by:

print in interface Printable

compile

public abstract void compile(Compilation comp,
                             Target target)

compileWithPosition

public final void compileWithPosition(Compilation comp,
                                      Target target)

Same as compile, but emit line number beforehard.

compileNotePosition

public final void compileNotePosition(Compilation comp,
                                      Target target)

Compile, but take note of line number.

compile

public final void compile(Compilation comp,
                          Type type)

setFile

public final void setFile(java.lang.String filename)

setLine

public final void setLine(int lineno,
                          int colno)

setLine

public final void setLine(int lineno)

getFile

public final java.lang.String getFile()

getLine

public final int getLine()

Get the line number of (the start of) this Expression. The "first" line is line 1.

getColumn

public final int getColumn()

getType

public Type getType()

Return the Type used to represent the values of this Expression.