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Michele Vivoda commented on JXPATH-163: --------------------------------------- Hi, >From XPath specification: http://www.w3.org/TR/xpath/#NT-PredicateExpr [8] Predicate ::= '[' PredicateExpr ']' [9] PredicateExpr ::= Expr A predicate filters a node-set with respect to an axis to produce a new node-set. For each node in the node-set to be filtered, the PredicateExpr is evaluated with that node as the context node, with the number of nodes in the node-set as the context size, and with the proximity position of the node in the node-set with respect to the axis as the context position; if PredicateExpr evaluates to true for that node, the node is included in the new node-set; otherwise, it is not included. A PredicateExpr is evaluated by evaluating the Expr and converting the result to a boolean. If the result is a number, the result will be converted to true if the number is equal to the context position and will be converted to false otherwise; if the result is not a number, then the result will be converted as if by a call to the boolean function. Thus a location path para[3] is equivalent to para[position()=3]. -------------- I read that if the Expr is a string, it is converted to true if the string is not empty, meaning 'any node' and so the first node is selected, if it were a "node set" selection instead of a "single node" then all nodes would have been selected. JXPath seems to comply with the spec. You may probably consider to use number() to force conversion to a number that then is checked against the position. /se:someArray[number($var)] > String variables cannot be used as indices > ------------------------------------------ > > Key: JXPATH-163 > URL: https://issues.apache.org/jira/browse/JXPATH-163 > Project: Commons JXPath > Issue Type: Bug > Affects Versions: 1.3 > Reporter: Alexander Koledzhikov > Priority: Minor > Attachments: commons-jxpath.patch > > > If I have a string variable, I cannot use it as an index in an xpath query. > For example, if var = "5", this query will return the 1st element, not the > fifth: > /se:someArray[$var] -- This message was sent by Atlassian JIRA (v6.1.5#6160)