library module: http://snelson.org.uk/functions/transform

transform.xq

An extensible transformation library for XQuery 3.0.

Author: John Snelson
Version: 0.9

Table of Contents

• Functions: tfm:mode#1, tfm:extend-mode#2, tfm:named-mode#1, tfm:named-extend-mode#2, tfm:named-rules#1, tfm:rule#2, tfm:rule#3, tfm:predicate-rule#2, tfm:resolver#1, tfm:pattern#1, tfm:pattern#2, tfm:param#2, tfm:param#3, tfm:get-param#2

Functions

tfm:mode#1

tfm:mode(
  $rules as (function(xs:string) as function(*)?)*
) as  function(node()*,function() as item()*?) as item()*

Returns a mode function, which can be called to perform the transformation specified by the rules passed in as arguments. Call tfm:rule(), or tfm:predicate-rule() to create rules to pass into this function.

Mode functions take the following arguments:

• $nodes as node()*: The context nodes to execute the mode on.
• $params as function() as item()*?: An rbtree.xq map of parameters passed to the mode, or the empty sequence. Can be constructed by tfm:param#2 and tfm:param#3.

Params

• $rules as (function(xs:string) as function(*)?)*: The sequence of rules to use to create the mode, in increasing precedence.

Returns

• function(node()*,function() as item()*?) as item()*: A mode function.

tfm:extend-mode#2

tfm:extend-mode(
  $mode as function(node()*,function() as item()*?) as item()*,
  $rules as (function(xs:string) as function(*)?)*
) as  function(node()*,function() as item()*?) as item()*

Returns a new mode function, which extends the transformation from the mode argument, adding the additional rules in higher precedence. Call tfm:rule(), or tfm:predicate-rule() to create rules to pass into this function.

Mode functions take the following arguments:

• $nodes as node()*: The context nodes to execute the mode on.
• $params as function() as item()*?: An rbtree.xq map of parameters passed to the mode, or the empty sequence. Can be constructed by tfm:param#2 and tfm:param#3.

Params

• $mode as function(node()*,function() as item()*?) as item()*: The mode to extend.

• $rules as (function(xs:string) as function(*)?)*: The sequence of rules to use to create the mode, in increasing precedence.

Returns

• function(node()*,function() as item()*?) as item()*: A mode function.

tfm:named-mode#1

tfm:named-mode(
  $name as xs:string*
) as  function(node()*,function() as item()*?) as item()*

Returns a mode function constructed from the functions annotated with the given name in the %tfm:rule() annotation.

Mode functions take the following arguments:

• $nodes as node()*: The context nodes to execute the mode on.
• $params as function() as item()*?: An rbtree.xq map of parameters passed to the mode, or the empty sequence. Can be constructed by tfm:param#2 and tfm:param#3.

Params

• $name as xs:string*: The name(s) used in the %tfm:rule() annotation in the functions for the mode to construct.

Returns

• function(node()*,function() as item()*?) as item()*: A mode function.

Errors

If reflection capabilites are not supported by your XQuery implementation.

tfm:named-extend-mode#2

tfm:named-extend-mode(
  $mode as function(node()*,function() as item()*?) as item()*,
  $name as xs:string*
) as  function(node()*,function() as item()*?) as item()*

Returns a new mode function, which extends the transformation from the mode argument, adding additional rules constructed from the functions annotated with the given name in the %tfm:rule() annotation.

Mode functions take the following arguments:

• $nodes as node()*: The context nodes to execute the mode on.
• $params as function() as item()*?: An rbtree.xq map of parameters passed to the mode, or the empty sequence. Can be constructed by tfm:param#2 and tfm:param#3.

Params

• $mode as function(node()*,function() as item()*?) as item()*: The mode to extend.

• $name as xs:string*: The name(s) used in the %tfm:rule() annotation in the functions for the mode to construct.

Returns

• function(node()*,function() as item()*?) as item()*: A mode function.

Errors

If reflection capabilites are not supported by your XQuery implementation.

tfm:named-rules#1

tfm:named-rules(
  $name as xs:string*
) as  (function(xs:string) as function(*)?)*

Returns a sequence of rules constructed from the functions annotated with the given name(s) in the %tfm:rule() annotation.

Params

• $name as xs:string*: The name(s) used in the %tfm:rule() annotation in the functions for the mode to construct.

Returns

• (function(xs:string) as function(*)?)*: A sequence of rules wrapped as functions, in increasing order by the priority from the %tfm:rule annotation.

Errors

If reflection capabilites are not supported by your XQuery implementation.

tfm:rule#2

tfm:rule(
  $pattern as xs:string,
  $action as function(*)
) as  function(xs:string) as function(*)?

Returns a rule constructed from the pattern and action specified. Rules are represented as a single function.

Action functions should take between 2 and 3 arguments. If the function takes fewer arguments, they are the arguments at the start of this list:

• $mode as function(node()*) as item()*: The mode function, used to re-apply the mode on further nodes. Can alternately be specified as type function(node()*,function() as item()*?) as item()*, which accepts parameters as the second argument.
• $context as node(): The context node that the rule is executed on.
• $params as function() as item()*?: An rbtree.xq map of parameters passed to the mode, or the empty sequence. Can be constructed by tfm:param#2 and tfm:param#3.
• $next-match as function() as item()*: The next-mode function. Can alternately be specified as type function(function() as item()*?) as item()*, which accepts parameters as the second argument.

Params

• $pattern as xs:string: The pattern string that the rule must match.

• $action as function(*): The action function to be executed when the rule is matched.

Returns

• function(xs:string) as function(*)?: The rule wrapped as a function.

tfm:rule#3

tfm:rule(
  $pattern as xs:string,
  $action as function(*),
  $resolver as item()
) as  function(xs:string) as function(*)?

Returns a rule constructed from the pattern and action specified. Rules are represented as a single function.

Action functions should take between 2 and 3 arguments. If the function takes fewer arguments, they are the arguments at the start of this list:

• $mode as function(node()*) as item()*: The mode function, used to re-apply the mode on further nodes. Can alternately be specified as type function(node()*,function() as item()*?) as item()*, which accepts parameters as the second argument.
• $context as node(): The context node that the rule is executed on.
• $params as function() as item()*?: An rbtree.xq map of parameters passed to the mode, or the empty sequence. Can be constructed by tfm:param#2 and tfm:param#3.
• $next-match as function() as item()*: The next-mode function. Can alternately be specified as type function(function() as item()*?) as item()*, which accepts parameters as the second argument.

Params

• $pattern as xs:string: The pattern string that the rule must match.

• $action as function(*): The action function to be executed when the rule is matched.

• $resolver as item(): Either an element from which to take the namespace bindings, or a function of type function(xs:string) as xs:QName.

Returns

• function(xs:string) as function(*)?: The rule wrapped as a function.

tfm:predicate-rule#2

tfm:predicate-rule(
  $predicate as function(*),
  $action as function(*)
) as  function(xs:string) as function(*)?

Returns a rule constructed from the predicate function and action specified. Rules are represented as a single function.

The predicate function takes a node as an argument and returns true if the node matches. Returning false or raising an error is considered a non-match. Typing the argument of the function provided with a SequenceType of element(), attribute(), etc. will result in the predicate function being optimized by only attempting to be matched against that type of name.

Action functions should take between 2 and 3 arguments. If the function takes fewer arguments, they are the arguments at the start of this list:

• $mode as function(node()*) as item()*: The mode function, used to re-apply the mode on further nodes. Can alternately be specified as type function(node()*,function() as item()*?) as item()*, which accepts parameters as the second argument.
• $context as node(): The context node that the rule is executed on.
• $params as function() as item()*?: An rbtree.xq map of parameters passed to the mode, or the empty sequence. Can be constructed by tfm:param#2 and tfm:param#3.
• $next-match as function() as item()*: The next-mode function. Can alternately be specified as type function(function() as item()*?) as item()*, which accepts parameters as the second argument.

Params

• $predicate as function(*)

• $action as function(*): The action function to be executed when the rule is matched.

Returns

• function(xs:string) as function(*)?: The rule wrapped as a function.

tfm:resolver#1

tfm:resolver(
  $element as element()
) as  function(xs:string) as xs:QName

Returns a prefix resolver function that resolves prefixes by looking them up in the namespace bindings of the element.

Params

• $element as element(): The element whose namespace bindings should be used.

Returns

• function(xs:string) as xs:QName: The resolver function.

tfm:pattern#1

tfm:pattern(
  $pattern as xs:string
) as  function(*)

Compiles the pattern given in the string argument to a predicate function, which takes a node as the argument, and returns true if the node matches the pattern. If the predicate returns false or raises an error, the node does not match the pattern.

Params

• $pattern as xs:string: The pattern string.

Returns

• function(*): The predicate function.

tfm:pattern#2

tfm:pattern(
  $pattern as xs:string,
  $resolver as item()
) as  function(*)

Compiles the pattern given in the string argument to a predicate function, which takes a node as the argument, and returns true if the node matches the pattern. If the predicate returns false or raises an error, the node does not match the pattern.

Params

• $pattern as xs:string: The pattern string.

• $resolver as item(): Either an element from which to take the namespace bindings, or a function of type function(xs:string) as xs:QName which resolves a lexical QName to an xs:QName.

Returns

• function(*): The predicate function.

tfm:param#2

tfm:param(
  $name as xs:string,
  $value as item()*
) as  function() as item()*

Helper function to allow simple construction of a parameters map suitable for passing to a mode function, given the parameter name and value.

Params

• $name as xs:string: The parameter name.

• $value as item()*: The parameter value.

Returns

• function() as item()*: An rbtree.xq map containing the parameter.

tfm:param#3

tfm:param(
  $params as function() as item()*?,
  $name as xs:string,
  $value as item()*
) as  function() as item()*

Helper function to allow simple construction of a parameters map suitable for passing to a mode function, given an existing map, the parameter name, and value.

Params

• $params as function() as item()*?: An existing rbtree.xq map of parameters, or the empty sequence.

• $name as xs:string: The parameter name.

• $value as item()*: The parameter value.

Returns

• function() as item()*: An rbtree.xq map containing the original parameters augmeneted with the new parameter.

tfm:get-param#2

tfm:get-param(
  $params as function() as item()*?,
  $name as xs:string
) as  item()*

Helper function to retrive a parameter from a parameters map.

Params

• $params as function() as item()*?: An existing rbtree.xq map of parameters, or the empty sequence.

• $name as xs:string: The parameter name.

Returns

• item()*: The parameter value, or empty sequence if not found.

Generated by xquerydoc