Returns True only if the expanded-name is the name of an instruction.
The argument must evaluate to a string that is a QName. The QName is expanded into an expanded-name using the namespace declarations in scope for the expression.
This function returns True for all XSLT instruction elements that are supported in this release. The function returns False for all XSLT non-instruction elements, and for those elements that are not supported in this release. Outside of XSLT, the function always returns False.
The following function call returns True (provided the
xsl prefix is mapped to the XSLT namespace).