Package org.basex.query.util.parse

Class LocalVars

java.lang.Object

org.basex.query.util.parse.LocalVars

public final class LocalVars
extends Object

Organizes local variables.

Author:

BaseX Team 2005-21, BSD License, Christian Gruen

Constructor Summary

Constructors

Constructor	Description
LocalVars(QueryParser parser)	Constructor.

Method Summary

Modifier and Type	Method	Description
Var	add(Var var)	Creates and registers a new local variable in the current scope.
void	closeScope(int marker)	Closes the sub-scope and marks all contained variables as inaccessible.
int	openScope()	Opens a new sub-scope inside the current one.
VarScope	popContext()	Pops one variable context from the stack.
void	pushContext(HashMap<Var,Expr> global)	Pushes a new variable context onto the stack.
ParseExpr	resolve(QNm name, InputInfo ii)	Resolves the referenced variable as a local or static variable and returns a reference to it.
VarRef	resolveLocal(QNm name, InputInfo ii)	Tries to resolve a local variable reference.

Methods inherited from class java.lang.Object

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

Constructor Details

LocalVars

public LocalVars(QueryParser parser)

Constructor.

Parameters:

parser - query parser

Method Details

add

public Var add(Var var)

Creates and registers a new local variable in the current scope.

Parameters:

var - variable to be added (can be null)

Returns:

variable

resolveLocal

public VarRef resolveLocal(QNm name,
 InputInfo ii)

Tries to resolve a local variable reference.

Parameters:

name - variable name

ii - input info

Returns:

variable reference or null

resolve

public ParseExpr resolve(QNm name,
 InputInfo ii)
                  throws QueryException

Resolves the referenced variable as a local or static variable and returns a reference to it. IF the variable is not declared, the specified error is thrown.

Parameters:

name - variable name

ii - input info

Returns:

referenced variable

Throws:

QueryException - if the variable isn't defined

pushContext

public void pushContext(HashMap<Var,Expr> global)

Pushes a new variable context onto the stack.

Parameters:

global - mapping for non-local variables

popContext

public VarScope popContext()

Pops one variable context from the stack.

Returns:

the removed context's variable scope

openScope

public int openScope()

Opens a new sub-scope inside the current one. The returned marker has to be supplied to the corresponding call to closeScope(int) in order to mark the variables as inaccessible.

Returns:

marker for the current bindings

closeScope

public void closeScope(int marker)

Closes the sub-scope and marks all contained variables as inaccessible.

Parameters:

marker - marker for the start of the sub-scope