Package org.basex.query.expr
Class Extension
java.lang.Object
org.basex.query.expr.ExprInfo
org.basex.query.expr.Expr
org.basex.query.expr.ParseExpr
org.basex.query.expr.Single
org.basex.query.expr.Extension
Pragma extension.
- Author:
- BaseX Team 2005-21, BSD License, Leo Woerteler
-
Field Summary
-
Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionbooleanaccept(ASTVisitor visitor) Traverses this expression, notifying the visitor of declared and used variables, and checking the tree for other recursive properties.voidcheckUp()Checks if the updating semantics are satisfied.Compiles and optimizes the expression, assigns types and cardinalities.copy(CompileContext cc, IntObjMap<Var> vm) Copies an expression.data()Returns the data reference bound to this expression.booleanThis function is e.g.booleanIndicates if an expression has one of the specified compiler properties.booleanChecks if an expression can be rewritten to an index access.Optimizes an already compiled expression without recompiling its sub-expressions.voidCreates a query plan.voidplan(QueryString qs) Creates a query string.value(QueryContext qc) Evaluates the expression and returns the resulting value.Methods inherited from class org.basex.query.expr.Single
count, exprSize, inline, inlineableMethods inherited from class org.basex.query.expr.ParseExpr
adoptType, atomValue, checkAllUp, checkNoEmpty, checkNoEmpty, checkNoneUp, checkNoUp, checkType, checkType, checkUp, copyType, ctxValue, ebv, item, iter, refineType, seqType, size, test, toArray, toArray, toAtomItem, toB64, toB64, toBin, toBin, toBoolean, toBoolean, toBytes, toBytes, toDouble, toDouble, toElem, toFloat, toFunc, toItem, toItem, toLong, toLong, toMap, toMap, toNode, toNode, toNodeOrNull, toNumber, toNumberOrNull, toQNm, toQNm, toToken, toToken, toTokenOrNull, toZeroTokenMethods inherited from class org.basex.query.expr.Expr
arg, args, atomItem, atomIter, data, ddo, funcType, hasFreeVars, isSimple, markTailCalls, mergeEbv, simplifyFor, typeCheck, uses, vacuous, visitAllMethods inherited from class org.basex.query.expr.ExprInfo
description, toErrorString, toString
-
Constructor Details
-
Extension
Constructor.- Parameters:
info- input infopragma- pragmaexpr- enclosed expression
-
-
Method Details
-
checkUp
Description copied from class:ExprChecks if the updating semantics are satisfied. This function is only called if any updating expression was found in the query.- Overrides:
checkUpin classSingle- Throws:
QueryException- query exception
-
compile
Description copied from class:ExprCompiles and optimizes the expression, assigns types and cardinalities.- Overrides:
compilein classSingle- Parameters:
cc- compilation context- Returns:
- optimized expression
- Throws:
QueryException- query exception
-
optimize
Description copied from class:ExprOptimizes an already compiled expression without recompiling its sub-expressions. -
value
Description copied from class:ExprEvaluates the expression and returns the resulting value. If this method is not implemented,Expr.item(QueryContext, InputInfo)must be implemented instead.- Overrides:
valuein classParseExpr- Parameters:
qc- query context- Returns:
- value
- Throws:
QueryException- query exception
-
copy
Description copied from class:ExprCopies an expression. Used for inlining functions, or for copying static queries. It is utilized byVarRef.inline(org.basex.query.InlineContext),FuncItem.inline(org.basex.query.expr.Expr[], org.basex.query.CompileContext),Closure.inline(org.basex.query.InlineContext)andStaticFunc.inline(org.basex.query.expr.Expr[], org.basex.query.CompileContext).- Specified by:
copyin classExpr- Parameters:
cc- compilation contextvm- mapping from old variable IDs to new variable copies. Required byClosure.copy(org.basex.query.CompileContext, org.basex.util.hash.IntObjMap<org.basex.query.var.Var>)andVarRef.copy(org.basex.query.CompileContext, org.basex.util.hash.IntObjMap<org.basex.query.var.Var>)- Returns:
- copied expression
-
has
Description copied from class:ExprIndicates if an expression has one of the specified compiler properties. This method must only be called at compile time. It is invoked to test properties of sub-expressions. It returnstrueif at least flag matches an expression. -
accept
Description copied from class:ExprTraverses this expression, notifying the visitor of declared and used variables, and checking the tree for other recursive properties. -
indexAccessible
Description copied from class:ExprChecks if an expression can be rewritten to an index access. If so, the index expression will be bound toIndexInfo.expr. This method will be called by thePathexpression.- Overrides:
indexAccessiblein classExpr- Parameters:
ii- index info- Returns:
- true if an index can be used
- Throws:
QueryException- query exception
-
data
Description copied from class:Expr -
equals
Description copied from class:SingleThis function is e.g. called by:Must be overwritten by implementing class.If.optimize(CompileContext),Switch.optimize(CompileContext),Typeswitch.optimize(CompileContext), in order to discard identical expressions.CmpR.mergeEbv(Expr, boolean, CompileContext)orCmpSR.mergeEbv(Expr, boolean, CompileContext), in order to merge expressions with identical input.CmpG.optimize(CompileContext)orCmpV.optimize(CompileContext), in order to pre-evaluate equality tests.CmpG.optimize(CompileContext)orPos.get(Expr, CmpV.OpV, InputInfo, CompileContext), in order to compare the start and end value.PathCache, in order to find identical root values at runtime.
-
plan
Description copied from class:ExprInfoCreates a query plan. -
plan
Description copied from class:ExprInfoCreates a query string.
-