ast
Class UnaryExpr

java.lang.Object
  ast.ASTNode
      ast.Expr
          ast.UnaryExpr

Direct Known Subclasses:

UnaryDecrExpr, UnaryIncrExpr, UnaryNegExpr, UnaryNotExpr

public abstract class UnaryExpr
extends Expr

The abstract UnaryExpr class represents unary expressions whose operand is an expression (i.e., this does not include new constructions). It can be either a negation expression ('-'), a complement expression ('!'), an increment expression ('++'), or a decrement expression ('--'). It contains an expression. Subclasses of this class can be handled similarly within the compiler, so most functionality can be implemented in the visitor method for this class.

See Also:

ASTNode, Expr

Field Summary

protected Expr

expr The expression

Fields inherited from class ast.ASTNode

charNum, lineNum, lineStr

Constructor Summary

UnaryExpr(int lineNum, Expr expr)
UnaryExpr constructor

Method Summary

abstract java.lang.Object	accept(Visitor v) Visitor method
Expr	getExpr() Get the expression
abstract java.lang.String	getOperandType() Get the operand type (e.g., "boolean") (must be defined by each subclass)
abstract java.lang.String	getOpName() Get the operation name (e.g., "!") (must be defined by each subclass)
abstract java.lang.String	getOpType() Get the operation type (e.g., "boolean") (must be defined by each subclass)
abstract boolean	isPostfix() Is this a postfix operator (as opposed to prefix)?

Methods inherited from class ast.Expr

getExprType, setExprType

Methods inherited from class ast.ASTNode

getLineNum

Methods inherited from class java.lang.Object

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

Field Detail

expr

protected Expr expr

The expression

Constructor Detail

UnaryExpr

public UnaryExpr(int lineNum,
                 Expr expr)

UnaryExpr constructor

Parameters:

lineNum - source line number corresponding to this AST node

expr - expression

Method Detail

getExpr

public Expr getExpr()

Get the expression

Returns:

expression

getOpName

public abstract java.lang.String getOpName()

Get the operation name (e.g., "!") (must be defined by each subclass)

Returns:

op name

getOpType

public abstract java.lang.String getOpType()

Get the operation type (e.g., "boolean") (must be defined by each subclass)

Returns:

op type

getOperandType

public abstract java.lang.String getOperandType()

Get the operand type (e.g., "boolean") (must be defined by each subclass)

Returns:

operand type

isPostfix

public abstract boolean isPostfix()

Is this a postfix operator (as opposed to prefix)?

Returns:

boolean indicating whether postfix operator

accept

public abstract java.lang.Object accept(Visitor v)

Visitor method

Specified by:

accept in class Expr

Parameters:

v - visitor object

Returns:

result of visiting this node

See Also:

Visitor