public final class Switch extends ParseExpr
Constructor and Description |
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Switch(InputInfo info,
Expr cond,
SwitchCase[] cases)
Constructor.
|
Modifier and Type | Method and Description |
---|---|
boolean |
accept(ASTVisitor visitor)
Traverses this expression, notifying the visitor of declared and used variables,
and checking the tree for other recursive properties.
|
void |
checkUp()
Checks if all updating expressions are correctly placed.
|
Expr |
compile(QueryContext qc,
VarScope scp)
Compiles and optimizes the expression, assigns types and cardinalities.
|
Expr |
copy(QueryContext qc,
VarScope scp,
IntObjMap<Var> vs)
Copies an expression.
|
VarUsage |
count(Var var)
Checks how often a variable is used in this expression.
|
int |
exprSize()
Counts the number of expressions in this expression's sub-tree.
|
boolean |
has(Expr.Flag flag)
Indicates if an expression has the specified compiler property.
|
Expr |
inline(QueryContext qc,
VarScope scp,
Var var,
Expr ex)
Inlines an expression into this one, replacing all references to the given variable.
|
boolean |
isVacuous()
Tests if this is a vacuous expression (empty sequence or error function).
|
Item |
item(QueryContext qc,
InputInfo ii)
Evaluates the expression and returns the resulting item,
or a
null reference if the expression yields an empty sequence. |
Iter |
iter(QueryContext qc)
Evaluates the expression and returns an iterator on the resulting items.
|
void |
markTailCalls(QueryContext qc)
Finds and marks tail calls, enabling TCO.
|
Expr |
optimize(QueryContext qc,
VarScope scp)
Optimizes an already compiled expression without recompiling its sub-expressions.
|
void |
plan(FElem plan)
Creates an expression tree.
|
boolean |
removable(Var var)
Checks if the specified variable is replaceable by a context value.
|
String |
toString() |
Value |
value(QueryContext qc)
Evaluates the expression and returns the resulting value.
|
atomItem, atomValue, checkAtomic, checkNoEmpty, checkNoEmpty, checkNoneUp, checkNoUp, checkType, compBln, copyType, ctxValue, ebv, optPre, optPre, preEval, seqType, seqType, size, test, toArray, toArray, toAtomItem, toB64, toB64, toBin, toBin, toBoolean, toBoolean, toBytes, toBytes, toDouble, toDouble, toElem, toEmptyNode, toEmptyToken, toFloat, toFunc, toItem, toLong, toLong, toMap, toMap, toNode, toNode, toNumber, toQNm, toQNm, toToken, toToken
atomIter, data, hasFreeVars, indexAccessible, inlineAll, isEmpty, isFunction, isValue, iterable, optimizeEbv, sameAs, typeCheck, uses, visitAll
addPlan, addPlan, description, planAttr, planElem, toErrorString
public Switch(InputInfo info, Expr cond, SwitchCase[] cases)
info
- input infocond
- conditioncases
- cases (last one is default case)public void checkUp() throws QueryException
Expr
checkUp
in class Expr
QueryException
- query exceptionpublic Expr compile(QueryContext qc, VarScope scp) throws QueryException
Expr
QueryContext.compile()
.compile
in class Expr
qc
- query contextscp
- variable scopeQueryException
- query exceptionpublic Expr optimize(QueryContext qc, VarScope scp) throws QueryException
Expr
optimize
in class Expr
qc
- query contextscp
- variable scopeQueryException
- query exceptionpublic Iter iter(QueryContext qc) throws QueryException
Expr
Expr.item(QueryContext, InputInfo)
must be implemented
by an expression, as it may be called by this method.iter
in class ParseExpr
qc
- query contextQueryException
- query exceptionpublic Value value(QueryContext qc) throws QueryException
Expr
value
in class ParseExpr
qc
- query contextQueryException
- query exceptionpublic Item item(QueryContext qc, InputInfo ii) throws QueryException
Expr
null
reference if the expression yields an empty sequence.
If this method is not overwritten, Expr.iter(QueryContext)
must be implemented by an
expression, as it may be called by this method.item
in class ParseExpr
qc
- query contextii
- input infonull
QueryException
- query exceptionpublic boolean isVacuous()
Expr
public boolean has(Expr.Flag flag)
Expr
true
if at least one test is successful.public boolean removable(Var var)
Expr
Preds.removable(org.basex.query.var.Var)
if one of the variables is used within a predicate.Path.removable(org.basex.query.var.Var)
if the variable occurs within the path.GFLWOR.compile(QueryContext, VarScope)
to rewrite where
clauses into predicates.public VarUsage count(Var var)
Expr
SwitchCase.countCases(org.basex.query.var.Var)
or (indirectly)
GFLWOR.inlineLets(org.basex.query.QueryContext, org.basex.query.var.VarScope)
.public Expr inline(QueryContext qc, VarScope scp, Var var, Expr ex) throws QueryException
Expr
GFLWOR.inlineLets(org.basex.query.QueryContext, org.basex.query.var.VarScope)
and For.toPredicate(org.basex.query.QueryContext, org.basex.query.var.VarScope, org.basex.query.expr.Expr)
,
and the variable reference is replaced in VarRef.inline(org.basex.query.QueryContext, org.basex.query.var.VarScope, org.basex.query.var.Var, org.basex.query.expr.Expr)
.inline
in class Expr
qc
- query context for reoptimizationscp
- variable scope for reoptimizationvar
- variable to replaceex
- expression to inlinenull
otherwiseQueryException
- query exceptionpublic Expr copy(QueryContext qc, VarScope scp, IntObjMap<Var> vs)
Expr
public void plan(FElem plan)
ExprInfo
public void markTailCalls(QueryContext qc)
Expr
markTailCalls
in class Expr
qc
- query context, null
if the changes should not be reportedpublic boolean accept(ASTVisitor visitor)
Expr
public int exprSize()
Expr
StaticFunc.inline(org.basex.query.QueryContext, org.basex.query.util.list.AnnList, org.basex.query.expr.Expr)
to check if an expression
is small enough to be inlined.Copyright © 2005–2015 BaseX Team. All rights reserved.