Class Handler

A handler for a ‘try’ statement.

This corresponds to a ‘catch block’ in the source. If the exception is of a type that can be handled by this ‘catch block’, then execution continues with the associated CatchBlock. Otherwise, execution continues with the next Handler.

This has no concrete representation in the source, but makes the control flow graph easier to use. For example in the following code:

try
{
  f();
} catch (std::exception &e) {
  g();
}

there is a handler that’s associated with the catch block and controls entry to it.

Import path

import cpp

Direct supertypes

Indirect supertypes

Known direct subtypes

Predicates

getAPrimaryQlClass	Gets the name of a primary CodeQL class to which this element belongs.
getBlock	Gets the block containing the implementation of this handler.
getParameter	Gets the parameter introduced by this ‘catch block’, if any.
getTryStmt	Gets the ‘try’ statement corresponding to this ‘catch block’.
mayBeGloballyImpure	Holds if it is possible that this statement is globally impure.
mayBeImpure	Holds if it is possible that this statement is impure. If we are not sure, then it holds.
toString	Gets a textual representation of this element.

Inherited predicates

findRootCause	Gets the source of this element: either itself or a macro that expanded to this element.	from Element
fromSource	Holds if this element may be from source. This predicate holds for all elements, except for those in the dummy file, whose name is the empty string. The dummy file contains declarations that are built directly into the compiler.	from Element
getAChild	Gets a child of this statement.	from Stmt
getAFalseSuccessor	Gets a node such that the control-flow edge `(this, result)` may be taken when this expression is false.	from ControlFlowNode
getAPredecessor	Gets a direct predecessor of this control-flow node, if any.	from ControlFlowNode
getASuccessor	Gets a direct successor of this control-flow node, if any.	from ControlFlowNode
getATrueSuccessor	Gets a node such that the control-flow edge `(this, result)` may be taken when this expression is true.	from ControlFlowNode
getAnAttribute	Gets an attribute of this statement, for example `[[clang::fallthrough]]`.	from Stmt
getAnImplicitDestructorCall	Gets a compiler-generated destructor call that is performed after this statement.	from Stmt
getBasicBlock	Gets the `BasicBlock` containing this control-flow node.	from ControlFlowNode
getChild	Gets the `n`th child of this statement.	from Stmt
getChildStmt	Gets a child statement of this statement.	from Stmt
getControlFlowScope	Gets the function containing this control-flow node.	from Stmt
getEnclosingBlock	Gets the nearest enclosing block of this statement in the source, if any.	from Stmt
getEnclosingElement	Gets the closest `Element` enclosing this one.	from Element
getEnclosingFunction	Gets the enclosing function of this statement, if any.	from Stmt
getEnclosingStmt	Gets the smallest statement containing this control-flow node.	from Stmt
getFile	Gets the primary file where this element occurs.	from Element
getFollowingStmt	Gets the statement following this statement in the same block, if any.	from Stmt
getGeneratingMacro	Gets a macro invocation that generates this entire statement.	from Stmt
getImplicitDestructorCall	Gets the `n`th compiler-generated destructor call that is performed after this statement, in order of destruction.	from Stmt
getLocation	Gets the primary location of this element.	from Stmt
getParent	Gets the parent of this statement, if any.	from Stmt
getParentScope	Gets the parent scope of this `Element`, if any. A scope is a `Type` (`Class` / `Enum`), a `Namespace`, a `BlockStmt`, a `Function`, or certain kinds of `Statement`.	from Element
getParentStmt	Gets the parent statement of this statement, if any.	from Stmt
getPrimaryQlClasses	Gets a comma-separated list of the names of the primary CodeQL classes to which this element belongs.	from ElementBase
hasChild	Holds if `e` is the `n`th child of this statement.	from Stmt
isAffectedByMacro	Holds if this element is affected in any way by a macro. All elements that are totally or partially generated by a macro are included, so this is a super-set of `isInMacroExpansion`.	from Element
isCompilerGenerated	Holds if this statement was generated by the compiler.	from Stmt
isCondition	Holds if this node is the top-level expression of a conditional statement, meaning that `this.getATrueSuccessor()` or `this.getAFalseSuccessor()` will have a result.	from ControlFlowNode
isFromTemplateInstantiation	Holds if this `Element` is a part of a template instantiation (but not the template itself).	from Element
isFromUninstantiatedTemplate	Holds if this `Element` is part of a template `template` (not if it is part of an instantiation of `template`). This means it is represented in the database purely as syntax and without guarantees on the presence or correctness of type-based operations such as implicit conversions.	from Element
isInMacroExpansion	Holds if this element comes from a macro expansion. Only elements that are entirely generated by a macro are included - for elements that partially come from a macro, see `isAffectedByMacro`.	from Element
isPure	Holds if this statement is side-effect free (a conservative approximation; that is, it may be side-effect free even if this predicate doesn’t hold).	from Stmt