[cxml-devel] cxml-stp usage
Greetings all, I'm a bit stumped by some of the STP functions and usage. The documentation is, well, a bit sparse, so it's not clear whether there really is a bug or I'm mis-interpreting what I'm reading. Here is a simple function that should return all the child nodes of an element with the local-name of 'RegressionModel': (defun function-name (document) "Return the PMML model type of the document" (stp:filter-recursively (stp:of-name "RegressionModel") (stp:first-child document))) According to the documentation of filter-recursively: Return a list of descendant nodes of node in pre-order, from which nodes that do not satisfy predicate have been removed.and that for of-name: This function creates a test function for nodes of this name.
The function returned will return T if the argument is an instance of attribute or element and has the specified local-name and namespace URI, and will return NIL otherwise.
If local-name is nil, only the namespace URI is considered for comparison.
and here's the local snippet of the xmls that I'm trying to filter for: #.(CXML-STP:ELEMENT
#| :PARENT of type ELEMENT |# :ATTRIBUTES '(#.(CXML-STP:ATTRIBUTE #| :PARENT of type ELEMENT |# :VALUE "PolynomialRegression" :LOCAL-NAME "algorithmName") #.(CXML-STP:ATTRIBUTE #| :PARENT of type ELEMENT |# :VALUE "regression" :LOCAL-NAME "functionName") #.(CXML-STP:ATTRIBUTE #| :PARENT of type ELEMENT |# :VALUE "KNIME Polynomial Regression" :LOCAL-NAME "modelName") #.(CXML-STP:ATTRIBUTE #| :PARENT of type ELEMENT |# :VALUE "s_s_temp" :LOCAL-NAME "targetFieldName")) :BASE-URI "file://+/Users/nunez/src/lisp/pmml/polynomial-regression.xml" :CHILDREN '(#.(CXML-STP:TEXT #| :PARENT of type ELEMENT |# :DATA " ")So, there's an attribute with a local-name that matches the value in of-name. Why is this function always returning NIL?
Is stp stable enough for production use? It's been a while since it's been updated. I'm new to XML with LISP, so if there's a better documented or easier way to process these documents, happy to take a different route. Finally, does anyone know why I need to pass the function the first child? Seem cxml-stp is getting tripped up on the first line of the xml file: <?xml version="1.0" encoding="UTF-8"?> and forcing me to manually grab the second element. Is there a convention or idiom I'm missing? Sample file attached. Cheers, - Steve
Hi, Quoting Steven Nunez (steve_nunez@yahoo.com):
Greetings all,
I'm a bit stumped by some of the STP functions and usage. The documentation is, well, a bit sparse, so it's not clear whether there really is a bug or I'm mis-interpreting what I'm reading. Here is a simple function that should return all the child nodes of an element with the local-name of 'RegressionModel':
(defun function-name (document) "Return the PMML model type of the document" (stp:filter-recursively (stp:of-name "RegressionModel") (stp:first-child document)))
The call to OF-NAME is the problem, it needs to be (stp:of-name "RegressionModel" "http://www.dmg.org/PMML-4_0") because:
According to the documentation of filter-recursively: Return a list of descendant nodes of node in pre-order, from which nodes that do not satisfy predicate have been removed.and that for of-name: This function creates a test function for nodes of this name.
The function returned will return T if the argument is an instance of attribute or element and has the specified local-name and namespace URI, and will return NIL otherwise.
If local-name is nil, only the namespace URI is considered for comparison.
your element is in the http://www.dmg.org/PMML-4_0 namespace, whereas you specified the empty namespace. Roughly speaking, local-name == SYMBOL-NAME namespace-uri == SYMBOL-PACKAGE I.e. just like distinct symbols in different packages have got nothing to do with each other just because they happen to have the same SYMBOL-NAME in Lisp, similarly in XML, two elements with the same local-name but a different namespace are considered distinct.
and here's the local snippet of the xmls that I'm trying to filter for: [...] So, there's an attribute with a local-name that matches the value in of-name. Why is this function always returning NIL?
An element with that local-name, right?
Is stp stable enough for production use? It's been a while since it's been updated. I'm new to XML with LISP, so if there's a better documented or easier way to process these documents, happy to take a different route.
I think STP was pretty much finished when it was first written, because it is basically a Common Lisp adaptation of XOM, so the design was clear from the start.
Finally, does anyone know why I need to pass the function the first child? Seem cxml-stp is getting tripped up on the first line of the xml file: <?xml version="1.0" encoding="UTF-8"?> and forcing me to manually grab the second element. Is there a convention or idiom I'm missing?
I see no reason why you would have to call stp:first-child. The example works without that call. d.
Hi David, Right, your explanation makes it clear. What's the convention/best practice/idiom for picking out the namespaces? Would be a bit repetitious to keep typing that out. Regards, - Steve ________________________________ From: David Lichteblau <david@lichteblau.com> To: "cxml-devel@common-lisp.net" <cxml-devel@common-lisp.net> Sent: Sunday, June 10, 2012 8:49 PM Subject: Re: [cxml-devel] cxml-stp usage Hi, Quoting Steven Nunez (steve_nunez@yahoo.com):
Greetings all,
I'm a bit stumped by some of the STP functions and usage. The documentation is, well, a bit sparse, so it's not clear whether there really is a bug or I'm mis-interpreting what I'm reading. Here is a simple function that should return all the child nodes of an element with the local-name of 'RegressionModel':
(defun function-name (document) "Return the PMML model type of the document" (stp:filter-recursively (stp:of-name "RegressionModel") (stp:first-child document)))
The call to OF-NAME is the problem, it needs to be (stp:of-name "RegressionModel" "http://www.dmg.org/PMML-4_0") because:
According to the documentation of filter-recursively: Return a list of descendant nodes of node in pre-order, from which nodes that do not satisfy predicate have been removed.and that for of-name: This function creates a test function for nodes of this name.
The function returned will return T if the argument is an instance of attribute or element and has the specified local-name and namespace URI, and will return NIL otherwise.
If local-name is nil, only the namespace URI is considered for comparison.
your element is in the http://www.dmg.org/PMML-4_0 namespace, whereas you specified the empty namespace. Roughly speaking, local-name == SYMBOL-NAME namespace-uri == SYMBOL-PACKAGE I.e. just like distinct symbols in different packages have got nothing to do with each other just because they happen to have the same SYMBOL-NAME in Lisp, similarly in XML, two elements with the same local-name but a different namespace are considered distinct.
and here's the local snippet of the xmls that I'm trying to filter for: [...] So, there's an attribute with a local-name that matches the value in of-name. Why is this function always returning NIL?
An element with that local-name, right?
Is stp stable enough for production use? It's been a while since it's been updated. I'm new to XML with LISP, so if there's a better documented or easier way to process these documents, happy to take a different route.
I think STP was pretty much finished when it was first written, because it is basically a Common Lisp adaptation of XOM, so the design was clear from the start.
Finally, does anyone know why I need to pass the function the first child? Seem cxml-stp is getting tripped up on the first line of the xml file: <?xml version="1.0" encoding="UTF-8"?> and forcing me to manually grab the second element. Is there a convention or idiom I'm missing?
I see no reason why you would have to call stp:first-child. The example works without that call. d.
On Jun 10, 2012, at 13:06 , Steven Nunez wrote:
Hi David,
Right, your explanation makes it clear. What's the convention/best practice/idiom for picking out the namespaces? Would be a bit repetitious to keep typing that out.
One easy way might be to use xuriella-xpath, which has xpath:with-namespaces - not sure if this is possible in your case.
participants (3)
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David Lichteblau -
Raymond Wiker -
Steven Nunez