net.sf.saxon.functions
public class ExecutableFunctionLibrary extends Object implements FunctionLibrary
Constructor Summary | |
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ExecutableFunctionLibrary(Configuration config) |
Method Summary | |
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void | addFunction(UserFunction fn)
Register a function with the function library |
Expression | bind(int nameCode, String uri, String local, Expression[] staticArgs)
Bind a function, given the URI and local parts of the function name,
and the list of expressions supplied as arguments. |
FunctionLibrary | copy()
This method creates a copy of a FunctionLibrary: if the original FunctionLibrary allows
new functions to be added, then additions to this copy will not affect the original, or
vice versa.
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boolean | isAvailable(int fingerprint, String uri, String local, int arity)
Test whether a function with a given name and arity is available. |
Parameters: nameCode The namepool nameCode of the function name. The uri and local name are also supplied (redundantly) to avoid fetching them from the name pool. uri The URI of the function name local The local part of the function name staticArgs The expressions supplied statically in the function call. The intention is that the static type of the arguments (obtainable via getItemType() and getCardinality() may be used as part of the binding algorithm.
Returns: An object representing the extension function to be called, if one is found; null if no extension function was found matching the required name and arity.
Throws: net.sf.saxon.trans.XPathException if a function is found with the required name and arity, but the implementation of the function cannot be loaded or used; or if an error occurs while searching for the function; or if this function library "owns" the namespace containing the function call, but no function was found.
Returns: a copy of this function library. This must be an instance of the original class.
Parameters: uri The URI of the function name local The local part of the function name arity The number of arguments. This is set to -1 in the case of the single-argument function-available() function; in this case the method should return true if there is some matching extension function, regardless of its arity.