## net.sf.saxon.functions
Class ConstructorFunctionLibrary

    java.lang.Object
      |
      +--net.sf.saxon.functions.ConstructorFunctionLibrary

All Implemented Interfaces:
  FunctionLibrary, java.io.Serializable

public class ConstructorFunctionLibrary
extends java.lang.Object
implements FunctionLibrary

The ConstructorFunctionLibrary represents the collection of constructor functions for atomic types. These are provided for the built-in types such as xs:integer and xs:date, and also for user-defined atomic types.

See Also:
  Serialized Form

Constructor Summary
`ConstructorFunctionLibrary(Configuration config)` Create a SystemFunctionLibrary

Method Summary
`Expression` `bind(int nameCode, java.lang.String uri, java.lang.String localName, Expression[] arguments)` Bind an extension function, given the URI and local parts of the function name, and the list of expressions supplied as arguments.
`boolean` `isAvailable(int fingerprint, java.lang.String uri, java.lang.String local, int arity)` Test whether a system function with a given name and arity is available.

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Constructor Detail

### ConstructorFunctionLibrary

    public ConstructorFunctionLibrary(Configuration config)

  Create a SystemFunctionLibrary

Parameters:
  `config` - the Configuration

Method Detail

### isAvailable

    public boolean isAvailable(int fingerprint,
                               java.lang.String uri,
                               java.lang.String local,
                               int arity)

  Test whether a system function with a given name and arity is available. This supports the function-available() function in XSLT. This method may be called either at compile time or at run time.

  Specified by:
    `isAvailable` in interface `FunctionLibrary`
  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.
    `fingerprint` - The namepool fingerprint of the function name. This must match the uri and localName; the information is provided redundantly to avoid repeated lookups in the name pool.

### bind

    public Expression bind(int nameCode,
                           java.lang.String uri,
                           java.lang.String localName,
                           Expression[] arguments)
                    throws XPathException

  Bind an extension function, given the URI and local parts of the function name, and the list of expressions supplied as arguments. This method is called at compile time.

  Specified by:
    `bind` in interface `FunctionLibrary`
  Parameters:
    `uri` - The URI of the function name
    `localName` - The local part of the function name
    `arguments` - 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.
    `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.
  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:
    `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.