 |
Qt 4.8
|
|
Qt 4.8
|
A compile time only AST node that changes the static base URI, used when xml:base attributes appears.
More...
#include <qstaticbaseuristore_p.h>
Properties | |
| const QUrl | m_baseURI |
A compile time only AST node that changes the static base URI, used when xml:base attributes appears.
Definition at line 72 of file qstaticbaseuristore_p.h.
| StaticBaseURIStore::StaticBaseURIStore | ( | const QUrl & | baseURI, |
| const Expression::Ptr & | operand | ||
| ) |
baseURI must be valid, not empty, and either relative or absolute.
Definition at line 51 of file qstaticbaseuristore.cpp.
|
virtual |
Implements QPatternist::Expression.
Definition at line 77 of file qstaticbaseuristore.cpp.
|
virtual |
Returns a list of Sequence Types, describing the type of each of the expression's operands. Hence, this function has a relationship to the operands() function:
- The lengths of the lists returned by expectedOperandTypes() and operands() should always be equal in length, since one cannot describe the type of a non-existent operand(and all operands must have type information). - A significant difference between the two functions is that while the type of objects in the list returned by operands() may vary between compilations/static context, simply because the particular Expression is part of different XPath expressions, the types in the list returned by expectedOperandTypes is always the same since the function/operator signature never changes.
This function should not be confused with staticType(), which returns the static type of the expression itself, not its operands. The function call is an expression where this is clear: the type of the return value is not the same as the arguments' types. The static type of the operands supplied to the expression can be determined via the staticType() function of the instances returned by operands().
If the expression has no operands, an empty list should be returned.
Implements QPatternist::Expression.
Definition at line 70 of file qstaticbaseuristore.cpp.
|
virtual |
Implements QPatternist::Expression.
Definition at line 65 of file qstaticbaseuristore.cpp.
|
virtual |
This implementation guarantees to never rewrite away this Expression, but at most rewrite it as a child of another expression(that presumably have a type checking role). It is therefore always safe to override this function and call this implementation and not worry about that this Expression becomes deleted.
Many Expressions override typeCheck() and performs optimizations, as opposed to doing it in the compress() stage. This is due to that the design of those Expressions often are tied to that certain simplifications are done at the typeCheck() stage of the compilation process or that it in some other way is related to what the typeCheck() do. Also, the earlier the AST can be simplified, the better the chances are for subsequent optimizations.
It is important that the super class's typeCheck() is called before doing any custom type checking, since the call can change the children(notably, the childrens' static types). For example, if the Expression, MyExpression in the example, does not match the required type, typeCheck returns the Expression wrapped in for example ItemVerifier, CardinalityVerifier, or both.
typeCheck() may be called many times. typeCheck() must either raise an error if this Expression is an invalid expression. Thus, it is guaranteed that an Expression is valid after typeCheck() is called.
| context | supplies information, such as namespace bindings and available function signatures, that can be needed at compilation time. context is guaranteed by the caller to never null. |
| reqType | the static type that this Expression must match when evaluated. reqType is guaranteed by the caller to never null. |
Public Functions inherited from reqType Reimplemented from QPatternist::Expression.
Definition at line 57 of file qstaticbaseuristore.cpp.
|
private |
Definition at line 88 of file qstaticbaseuristore_p.h.
Referenced by typeCheck().