proof.parse
Class SymbolTable

java.lang.Object
  |
  +--proof.parse.SymbolTable

public class SymbolTable

extends java.lang.Object

A simple symbol table, using a Hashtable, and Vectors for scoping.

Constructor Summary

SymbolTable()
Constructor.

Method Summary

void	declare(java.lang.String name) Declare a variable, creating a new Var object with the given name.
void	declare(Var x) Declare a variable, which already is a Var object.
Var	lookup(java.lang.String name) Look up a variable.
void	undeclare(java.lang.String name) "Undeclare" a variable, removing it from scope.

Methods inherited from class java.lang.Object

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

Constructor Detail

SymbolTable

public SymbolTable()

Constructor.

Method Detail

declare

public void declare(java.lang.String name)

Declare a variable, creating a new Var object with the given name.

Parameters:

name - the name of the variable

declare

public void declare(Var x)

Declare a variable, which already is a Var object. (this may go away...)

Parameters:

x - the Var object in question

undeclare

public void undeclare(java.lang.String name)

"Undeclare" a variable, removing it from scope. Should be called when we're done parsing some construct.

Parameters:

name - the name of the variable to undeclare.

lookup

public Var lookup(java.lang.String name)

Look up a variable.

Parameters:

name - the name of the variable to look up

Returns:

that variable, or null if it wasn't found.