SummaryNo overview generated for ‘xpath.js‘
| Method Summary | static void | assert(b)
| static void | copyArray(dst, src)
| static Object | el(i)
| static Object | makeAbbrevStep(abbrev)
| static Object | makeArgumentExpr(comma, expr)
| static Object | makeBinaryExpr(expr1, op, expr2)
| static Object | makeFilterExpr(expr, predicates)
| static Object | makeFunctionCallExpr1(name, pareno, parenc)
| static Object | makeFunctionCallExpr2(name, pareno, arg1, args, parenc)
| static Object | makeLiteralExpr(token)
| static Object | makeLocationExpr1(slash, rel)
| static Object | makeLocationExpr2(dslash, rel)
| static Object | makeLocationExpr3(slash)
| static Object | makeLocationExpr4(dslash)
| static Object | makeLocationExpr5(step)
| static Object | makeLocationExpr6(rel, slash, step)
| static Object | makeLocationExpr7(rel, dslash, step)
| static Object | makeNodeTestExpr1(asterisk)
| static Object | makeNodeTestExpr2(ncname, colon, asterisk)
| static Object | makeNodeTestExpr3(qname)
| static Object | makeNodeTestExpr4(typeo, parenc)
| static Object | makeNodeTestExpr5(typeo, target, parenc)
| static Object | makeNumberExpr(token)
| static Object | makePathExpr1(filter, slash, rel)
| static Object | makePathExpr2(filter, dslash, rel)
| static Object | makePredicateExpr(pareno, expr, parenc)
| static Object | makePrimaryExpr(pareno, expr, parenc)
| static Object | makeSimpleExpr(expr)
| static Object | makeSimpleExpr2(expr)
| static Object | makeStepExpr1(dot)
| static Object | makeStepExpr2(ddot)
| static Object | makeStepExpr3(axisname, axis, nodetest)
| static Object | makeStepExpr4(at, nodetest)
| static Object | makeStepExpr5(nodetest)
| static Object | makeStepExpr6(step, predicate)
| static Object | makeTokenExpr(m)
| static Object | makeUnaryMinusExpr(minus, expr)
| static Object | makeUnionExpr(expr1, pipe, expr2)
| static Object | makeVariableReference(dollar, name)
| static void | mapExec(array, func)
| static Object | mapExpr(array, func)
| static Object | passExpr(e)
| static Object | px(x)
| static void | reverseInplace(array)
| static Object | stackToString(stack)
| static Object | stringSplit(s, c)
| static Object | xmlEscapeAttr(s)
| static Object | xmlEscapeTags(s)
| static Object | xmlEscapeText(s)
| static Object | xmlText(node)
| static Object | xmlValue(node)
| static Object | xpathCacheLookup(expr)
| static void | xpathCollectDescendants(nodelist, node)
| static void | xpathCollectDescendantsReverse(nodelist, node)
| static Object | xpathDomEval(expr, node)
| static Object | xpathGrammarPrecedence(frame)
| static Object | xpathMatchStack(stack, pattern)
| static Object | xpathParse(expr)
| static void | xpathParseInit()
| static Object | xpathReduce(stack, ahead)
| static void | xpathSort(input, sort)
| static Object | xpathSortByKey(v1, v2)
| static void | xPathStep(nodes, steps, step, input, ctx)
| static Object | xpathTokenPrecedence(tag)
|
/* xpath.js - Revision: Spry Preview Release 1.3 */// Copyright (c) 2005, Google Inc.// All rights reserved.// // Redistribution and use in source and binary forms, with or without// modification, are permitted provided that the following conditions are// met:// // * Redistributions of source code must retain the above copyright// notice, this list of conditions and the following disclaimer.// // * Redistributions in binary form must reproduce the above copyright// notice, this list of conditions and the following disclaimer in the// documentation and/or other materials provided with the// distribution.// // * Neither the name of Google Inc. nor the names of its contributors// may be used to endorse or promote products derived from this// software without specific prior written permission.// // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.//// An XPath parser and evaluator written in JavaScript. The// implementation is complete except for functions handling// namespaces.//// Reference: [XPATH] XPath Specification// <http://www./TR/1999/REC-xpath-19991116>.////// The API of the parser has several parts://// 1. The parser function xpathParse() that takes a string and returns// an expession object.//// 2. The expression object that has an evaluate() method to evaluate the// XPath expression it represents. (It is actually a hierarchy of// objects that resembles the parse tree, but an application will call// evaluate() only on the top node of this hierarchy.)//// 3. The context object that is passed as an argument to the evaluate()// method, which represents the DOM context in which the expression is// evaluated.//// 4. The value object that is returned from evaluate() and represents// values of the different types that are defined by XPath (number,// string, boolean, and node-set), and allows to convert between them.//// These parts are near the top of the file, the functions and data// that are used internally follow after them.////// TODO(mesch): add jsdoc comments. Use more coherent naming.////// Author: Steffen Meschkat <mesch@google.com>// The entry point for the parser.//// @param expr a string that contains an XPath expression.// @return an expression object that can be evaluated with an// expression context.function xpathParse(expr) {if (xpathdebug) {
Log.write(‘XPath parse ‘ + expr);
}
xpathParseInit();
var cached = xpathCacheLookup(expr);if (cached) {if (xpathdebug) {
Log.write(‘ ... cached‘);
}return cached;
}// Optimize for a few common cases: simple attribute node tests// (@id), simple element node tests (page), variable references// ($address), numbers (4), multi-step path expressions where each// step is a plain element node test// (page/overlay/locations/location).if (expr.match(/^(\$|@)?\w+$/i)) {
var ret = makeSimpleExpr(expr);
xpathParseCache[expr] = ret;if (xpathdebug) {
Log.write(‘ ... simple‘);
}return ret;
}if (expr.match(/^\w+(\/\w+)*$/i)) {
var ret = makeSimpleExpr2(expr);
xpathParseCache[expr] = ret;if (xpathdebug) {
Log.write(‘ ... simple 2‘);
}return ret;
}
var cachekey = expr; // expr is modified during parseif (xpathdebug) {
Timer.start(‘XPath parse‘, cachekey);
}
var stack = [];
var ahead = null;
var previous = null;
var done = false;
var parse_count = 0;
var lexer_count = 0;
var reduce_count = 0;while (!done) {
parse_count++;
expr = expr.replace(/^\s*/, ‘‘);
previous = ahead;
ahead = null;
var rule = null;
var match = ‘‘;for (var i = 0; i < xpathTokenRules.length; ++i) {
var result = xpathTokenRules[i].re.exec(expr);
lexer_count++;if (result && result.length > 0 && result[0].length > match.length) {
rule = xpathTokenRules[i];
match = result[0];
break;
}
}// Special case: allow operator keywords to be element and// variable names.// NOTE(mesch): The parser resolves conflicts by looking ahead,// and this is the only case where we look back to// disambiguate. So this is indeed something different, and// looking back is usually done in the lexer (via states in the// general case, called "start conditions" in flex(1)). Also,the// conflict resolution in the parser is not as robust as it could// be, so I‘d like to keep as much off the parser as possible (all// these precedence values should be computed from the grammar// rules and possibly associativity declarations, as in bison(1),// and not explicitly set.if (rule &&
(rule == TOK_DIV ||
rule == TOK_MOD ||
rule == TOK_AND ||
rule == TOK_OR) &&
(!previous ||
previous.tag == TOK_AT ||
previous.tag == TOK_DSLASH ||
previous.tag == TOK_SLASH ||
previous.tag == TOK_AXIS ||
previous.tag == TOK_DOLLAR)) {
rule = TOK_QNAME;
}if (rule) {
expr = expr.substr(match.length);if (xpathdebug) {
Log.write(‘token: ‘ + match + ‘ -- ‘ + rule.label);
}
ahead = {
tag: rule,
match: match,
prec: rule.prec ? rule.prec : 0, // || 0 is removed by the compilerexpr: makeTokenExpr(match)
};
} else {if (xpathdebug) {
Log.write(‘DONE‘);
}
done = true;
}while (xpathReduce(stack, ahead)) {
reduce_count++;if (xpathdebug) {
Log.write(‘stack: ‘ + stackToString(stack));
}
}
}if (xpathdebug) {
Log.write(stackToString(stack));
}if (stack.length != 1) {
throw ‘XPath parse error ‘ + cachekey + ‘:\n‘ + stackToString(stack);
}
var result = stack[0].expr;
xpathParseCache[cachekey] = result;if (xpathdebug) {
Timer.end(‘XPath parse‘, cachekey);
}if (xpathdebug) {
Log.write(‘XPath parse: ‘ + parse_count + ‘ / ‘ +
lexer_count + ‘ / ‘ + reduce_count);
}return result;
}
var xpathParseCache = {};function xpathCacheLookup(expr) {return xpathParseCache[expr];
}function xpathReduce(stack, ahead) {
var cand = null;if (stack.length > 0) {
var top = stack[stack.length-1];
var ruleset = xpathRules[top.tag.key];if (ruleset) {for (var i = 0; i < ruleset.length; ++i) {
var rule = ruleset[i];
var match = xpathMatchStack(stack, rule[1]);if (match.length) {
cand = {
tag: rule[0],
rule: rule,
match: match
};
cand.prec = xpathGrammarPrecedence(cand);
break;
}
}
}
}
var ret;if (cand && (!ahead || cand.prec > ahead.prec ||
(ahead.tag.left && cand.prec >= ahead.prec))) {for (var i = 0; i < cand.match.matchlength; ++i) {
stack.pop();
}if (xpathdebug) {
Log.write(‘reduce ‘ + cand.tag.label + ‘ ‘ + cand.prec +‘ ahead ‘ + (ahead ? ahead.tag.label + ‘ ‘ + ahead.prec +
(ahead.tag.left ? ‘ left‘ : ‘‘)
: ‘ none ‘));
}
var matchexpr = mapExpr(cand.match, function(m) { return m.expr; });
cand.expr = cand.rule[3].apply(null, matchexpr);
stack.push(cand);
ret = true;
} else {if (ahead) {if (xpathdebug) {
Log.write(‘shift ‘ + ahead.tag.label + ‘ ‘ + ahead.prec +
(ahead.tag.left ? ‘ left‘ : ‘‘) +‘ over ‘ + (cand ? cand.tag.label + ‘ ‘ +
cand.prec : ‘ none‘));
}
stack.push(ahead);
}
ret = false;
}return ret;
}function xpathMatchStack(stack, pattern) {// NOTE(mesch): The stack matches for variable cardinality are// greedy but don‘t do backtracking. This would be an issue only// with rules of the form A* A, i.e. with an element with variable// cardinality followed by the same element. Since that doesn‘t// occur in the grammar at hand, all matches on the stack are// unambiguous.var S = stack.length;
var P = pattern.length;
var p, s;
var match = [];
match.matchlength = 0;
var ds = 0;for (p = P - 1, s = S - 1; p >= 0 && s >= 0; --p, s -= ds) {
ds = 0;
var qmatch = [];if (pattern[p] == Q_MM) {
p -= 1;
match.push(qmatch);while (s - ds >= 0 && stack[s - ds].tag == pattern[p]) {
qmatch.push(stack[s - ds]);
ds += 1;
match.matchlength += 1;
}
} else if (pattern[p] == Q_01) {
p -= 1;
match.push(qmatch);while (s - ds >= 0 && ds < 2 && stack[s - ds].tag == pattern[p]) {
qmatch.push(stack[s - ds]);
ds += 1;
match.matchlength += 1;
}
} else if (pattern[p] == Q_1M) {
p -= 1;
match.push(qmatch);if (stack[s].tag == pattern[p]) {while (s - ds >= 0 && stack[s - ds].tag == pattern[p]) {
qmatch.push(stack[s - ds]);
ds += 1;
match.matchlength += 1;
}
} else {return [];
}
} else if (stack[s].tag == pattern[p]) {
match.push(stack[s]);
ds += 1;
match.matchlength += 1;
} else {return [];
}
reverseInplace(qmatch);
qmatch.expr = mapExpr(qmatch, function(m) { return m.expr; });
}
reverseInplace(match);if (p == -1) {return match;
} else {return [];
}
}function xpathTokenPrecedence(tag) {return tag.prec || 2;
}function xpathGrammarPrecedence(frame) {
var ret = 0;if (frame.rule) { /* normal reduce */if (frame.rule.length >= 3 && frame.rule[2] >= 0) {
ret = frame.rule[2];
} else {for (var i = 0; i < frame.rule[1].length; ++i) {
var p = xpathTokenPrecedence(frame.rule[1][i]);
ret = Math.max(ret, p);
}
}
} else if (frame.tag) { /* TOKEN match */ret = xpathTokenPrecedence(frame.tag);
} else if (frame.length) { /* Q_ match */for (var j = 0; j < frame.length; ++j) {
var p = xpathGrammarPrecedence(frame[j]);
ret = Math.max(ret, p);
}
}return ret;
}function stackToString(stack) {
var ret = ‘‘;for (var i = 0; i < stack.length; ++i) {if (ret) {
ret += ‘\n‘;
}
ret += stack[i].tag.label;
}return ret;
}// XPath expression evaluation context. An XPath context consists of a// DOM node, a list of DOM nodes that contains this node, a number// that represents the position of the single node in the list, and a// current set of variable bindings. (See XPath spec.)//// The interface of the expression context://// Constructor -- gets the node, its position, the node set it// belongs to, and a parent context as arguments. The parent context// is used to implement scoping rules for variables: if a variable// is not found in the current context, it is looked for in the// parent context, recursively. Except for node, all arguments have// default values: default position is 0, default node set is the// set that contains only the node, and the default parent is null.//// Notice that position starts at 0 at the outside interface;// inside XPath expressions this shows up as position()=1.//// clone() -- creates a new context with the current context as// parent. If passed as argument to clone(), the new context has a// different node, position, or node set. What is not passed is// inherited from the cloned context.//// setVariable(name, expr) -- binds given XPath expression to the// name.//// getVariable(name) -- what the name says.//// setNode(node, position) -- sets the context to the new node and// its corresponding position. Needed to implement scoping rules for// variables in XPath. (A variable is visible to all subsequent// siblings, not only to its children.)function ExprContext(node, position, nodelist, parent) {this.node = node;this.position = position || 0;this.nodelist = nodelist || [ node ];this.variables = {};this.parent = parent || null;this.root = parent ? parent.root : node.ownerDocument;
}
ExprContext.prototype.clone = function(node, position, nodelist) {return new
ExprContext(node || this.node,
typeof position != ‘undefined‘ ? position : this.position,
nodelist || this.nodelist, this);
};
ExprContext.prototype.setVariable = function(name, value) {this.variables[name] = value;
};
ExprContext.prototype.getVariable = function(name) {if (typeof this.variables[name] != ‘undefined‘) {return this.variables[name];
} else if (this.parent) {return this.parent.getVariable(name);
} else {return null;
}
}
ExprContext.prototype.setNode = function(node, position) {this.node = node;this.position = position;
}// XPath expression values. They are what XPath expressions evaluate// to. Strangely, the different value types are not specified in the// XPath syntax, but only in the semantics, so they don‘t show up as// nonterminals in the grammar. Yet, some expressions are required to// evaluate to particular types, and not every type can be coerced// into every other type. Although the types of XPath values are// similar to the types present in JavaScript, the type coercion rules// are a bit peculiar, so we explicitly model XPath types instead of// mapping them onto JavaScript types. (See XPath spec.)//// The four types are://// StringValue//// NumberValue//// BooleanValue//// NodeSetValue//// The common interface of the value classes consists of methods that// implement the XPath type coercion rules://// stringValue() -- returns the value as a JavaScript String,//// numberValue() -- returns the value as a JavaScript Number,//// booleanValue() -- returns the value as a JavaScript Boolean,//// nodeSetValue() -- returns the value as a JavaScript Array of DOM// Node objects.//function StringValue(value) {this.value = value;this.type = ‘string‘;
}
StringValue.prototype.stringValue = function() {return this.value;
}
StringValue.prototype.booleanValue = function() {return this.value.length > 0;
}
StringValue.prototype.numberValue = function() {return this.value - 0;
}
StringValue.prototype.nodeSetValue = function() {
throw this + ‘ ‘ + Error().stack;
}function BooleanValue(value) {this.value = value;this.type = ‘boolean‘;
}
BooleanValue.prototype.stringValue = function() {return ‘‘ + this.value;
}
BooleanValue.prototype.booleanValue = function() {return this.value;
}
BooleanValue.prototype.numberValue = function() {return this.value ? 1 : 0;
}
BooleanValue.prototype.nodeSetValue = function() {
throw this + ‘ ‘ + Error().stack;
}function NumberValue(value) {this.value = value;this.type = ‘number‘;
}
NumberValue.prototype.stringValue = function() {return ‘‘ + this.value;
}
NumberValue.prototype.booleanValue = function() {return !!this.value;
}
NumberValue.prototype.numberValue = function() {return this.value - 0;
}
NumberValue.prototype.nodeSetValue = function() {
throw this + ‘ ‘ + Error().stack;
}function NodeSetValue(value) {this.value = value;this.type = ‘node-set‘;
}
NodeSetValue.prototype.stringValue = function() {if (this.value.length == 0) {return ‘‘;
} else {return xmlValue(this.value[0]);
}
}
NodeSetValue.prototype.booleanValue = function() {return this.value.length > 0;
}
NodeSetValue.prototype.numberValue = function() {return this.stringValue() - 0;
}
NodeSetValue.prototype.nodeSetValue = function() {return this.value;
};// XPath expressions. They are used as nodes in the parse tree and// possess an evaluate() method to compute an XPath value given an XPath// context. Expressions are returned from the parser. Teh set of// expression classes closely mirrors the set of non terminal symbols// in the grammar. Every non trivial nonterminal symbol has a// corresponding expression class.//// The common expression interface consists of the following methods://// evaluate(context) -- evaluates the expression, returns a value.//// toString() -- returns the XPath text representation of the// expression (defined in xsltdebug.js).//// parseTree(indent) -- returns a parse tree representation of the// expression (defined in xsltdebug.js).function TokenExpr(m) {this.value = m;
}
TokenExpr.prototype.evaluate = function() {return new StringValue(this.value);
};function LocationExpr() {this.absolute = false;this.steps = [];
}
LocationExpr.prototype.appendStep = function(s) {this.steps.push(s);
}
LocationExpr.prototype.prependStep = function(s) {
var steps0 = this.steps;this.steps = [ s ];for (var i = 0; i < steps0.length; ++i) {this.steps.push(steps0[i]);
}
};
LocationExpr.prototype.evaluate = function(ctx) {
var start;if (this.absolute) {
start = ctx.root;
} else {
start = ctx.node;
}
var nodes = [];
xPathStep(nodes, this.steps, 0, start, ctx);return new NodeSetValue(nodes);
};function xPathStep(nodes, steps, step, input, ctx) {
var s = steps[step];
var ctx2 = ctx.clone(input);
var nodelist = s.evaluate(ctx2).nodeSetValue();for (var i = 0; i < nodelist.length; ++i) {if (step == steps.length - 1) {
nodes.push(nodelist[i]);
} else {
xPathStep(nodes, steps, step + 1, nodelist[i], ctx);
}
}
}function StepExpr(axis, nodetest, predicate) {this.axis = axis;this.nodetest = nodetest;this.predicate = predicate || [];
}
StepExpr.prototype.appendPredicate = function(p) {this.predicate.push(p);
}
StepExpr.prototype.evaluate = function(ctx) {
var input = ctx.node;
var nodelist = [];// NOTE(mesch): When this was a switch() statement, it didn‘t work// in Safari/2.0. Not sure why though; it resulted in the JavaScript// console output "undefined" (without any line number or so).if (this.axis == xpathAxis.ANCESTOR_OR_SELF) {
nodelist.push(input);for (var n = input.parentNode; n; n = input.parentNode) {
nodelist.push(n);
}
} else if (this.axis == xpathAxis.ANCESTOR) {for (var n = input.parentNode; n; n = input.parentNode) {
nodelist.push(n);
}
} else if (this.axis == xpathAxis.ATTRIBUTE) {
copyArray(nodelist, input.attributes);
} else if (this.axis == xpathAxis.CHILD) {
copyArray(nodelist, input.childNodes);
} else if (this.axis == xpathAxis.DESCENDANT_OR_SELF) {
nodelist.push(input);
xpathCollectDescendants(nodelist, input);
} else if (this.axis == xpathAxis.DESCENDANT) {
xpathCollectDescendants(nodelist, input);
} else if (this.axis == xpathAxis.FOLLOWING) {for (var n = input.parentNode; n; n = n.parentNode) {for (var nn = n.nextSibling; nn; nn = nn.nextSibling) {
nodelist.push(nn);
xpathCollectDescendants(nodelist, nn);
}
}
} else if (this.axis == xpathAxis.FOLLOWING_SIBLING) {for (var n = input.nextSibling; n; n = input.nextSibling) {
nodelist.push(n);
}
} else if (this.axis == xpathAxis.NAMESPACE) {
alert(‘not implemented: axis namespace‘);
} else if (this.axis == xpathAxis.PARENT) {if (input.parentNode) {
nodelist.push(input.parentNode);
}
} else if (this.axis == xpathAxis.PRECEDING) {for (var n = input.parentNode; n; n = n.parentNode) {for (var nn = n.previousSibling; nn; nn = nn.previousSibling) {
nodelist.push(nn);
xpathCollectDescendantsReverse(nodelist, nn);
}
}
} else if (this.axis == xpathAxis.PRECEDING_SIBLING) {for (var n = input.previousSibling; n; n = input.previousSibling) {
nodelist.push(n);
}
} else if (this.axis == xpathAxis.SELF) {
nodelist.push(input);
} else {
throw ‘ERROR -- NO SUCH AXIS: ‘ + this.axis;
}// process node testvar nodelist0 = nodelist;
nodelist = [];for (var i = 0; i < nodelist0.length; ++i) {
var n = nodelist0[i];if (this.nodetest.evaluate(ctx.clone(n, i, nodelist0)).booleanValue()) {
nodelist.push(n);
}
}// process predicatesfor (var i = 0; i < this.predicate.length; ++i) {
var nodelist0 = nodelist;
nodelist = [];for (var ii = 0; ii < nodelist0.length; ++ii) {
var n = nodelist0[ii];if (this.predicate[i].evaluate(ctx.clone(n, ii, nodelist0)).booleanValue()) {
nodelist.push(n);
}
}
}return new NodeSetValue(nodelist);
};function NodeTestAny() {this.value = new BooleanValue(true);
}
NodeTestAny.prototype.evaluate = function(ctx) {return this.value;
};function NodeTestElement() {}
NodeTestElement.prototype.evaluate = function(ctx) {return new BooleanValue(ctx.node.nodeType == DOM_ELEMENT_NODE);
}function NodeTestText() {}
NodeTestText.prototype.evaluate = function(ctx) {return new BooleanValue(ctx.node.nodeType == DOM_TEXT_NODE);
}function NodeTestComment() {}
NodeTestComment.prototype.evaluate = function(ctx) {return new BooleanValue(ctx.node.nodeType == DOM_COMMENT_NODE);
}function NodeTestPI(target) {this.target = target;
}
NodeTestPI.prototype.evaluate = function(ctx) {return new
BooleanValue(ctx.node.nodeType == DOM_PROCESSING_INSTRUCTION_NODE &&
(!this.target || ctx.node.nodeName == this.target));
}function NodeTestNC(nsprefix) {this.regex = new RegExp("^" + nsprefix + ":");this.nsprefix = nsprefix;
}
NodeTestNC.prototype.evaluate = function(ctx) {
var n = ctx.node;return new BooleanValue(this.regex.match(n.nodeName));
}function NodeTestName(name) {this.name = name;
}
NodeTestName.prototype.evaluate = function(ctx) {
var n = ctx.node;return new BooleanValue(n.nodeName == this.name);
}function PredicateExpr(expr) {this.expr = expr;
}
PredicateExpr.prototype.evaluate = function(ctx) {
var v = this.expr.evaluate(ctx);if (v.type == ‘number‘) {// NOTE(mesch): Internally, position is represented starting with// 0, however in XPath position starts with 1. See functions// position() and last().return new BooleanValue(ctx.position == v.numberValue() - 1);
} else {return new BooleanValue(v.booleanValue());
}
};function FunctionCallExpr(name) {this.name = name;this.args = [];
}
FunctionCallExpr.prototype.appendArg = function(arg) {this.args.push(arg);
};
FunctionCallExpr.prototype.evaluate = function(ctx) {
var fn = ‘‘ + this.name.value;
var f = this.xpathfunctions[fn];if (f) {return f.call(this, ctx);
} else {
Log.write(‘XPath NO SUCH FUNCTION ‘ + fn);return new BooleanValue(false);
}
};
FunctionCallExpr.prototype.xpathfunctions = {‘last‘: function(ctx) {
assert(this.args.length == 0);// NOTE(mesch): XPath position starts at 1.return new NumberValue(ctx.nodelist.length);
},‘position‘: function(ctx) {
assert(this.args.length == 0);// NOTE(mesch): XPath position starts at 1.return new NumberValue(ctx.position + 1);
},‘count‘: function(ctx) {
assert(this.args.length == 1);
var v = this.args[0].evaluate(ctx);return new NumberValue(v.nodeSetValue().length);
},‘id‘: function(ctx) {
assert(this.args.length == 1);
var e = this.args.evaluate(ctx);
var ret = [];
var ids;if (e.type == ‘node-set‘) {
ids = [];for (var i = 0; i < e.length; ++i) {
var v = xmlValue(e[i]).split(/\s+/);for (var ii = 0; ii < v.length; ++ii) {
ids.push(v[ii]);
}
}
} else {
ids = e.split(/\s+/);
}
var d = ctx.node.ownerDocument;for (var i = 0; i < ids.length; ++i) {
var n = d.getElementById(ids[i]);if (n) {
ret.push(n);
}
}return new NodeSetValue(ret);
},‘local-name‘: function(ctx) {
alert(‘not implmented yet: XPath function local-name()‘);
},‘namespace-uri‘: function(ctx) {
alert(‘not implmented yet: XPath function namespace-uri()‘);
},‘name‘: function(ctx) {
assert(this.args.length == 1 || this.args.length == 0);
var n;if (this.args.length == 0) {
n = [ ctx.node ];
} else {
n = this.args[0].evaluate(ctx).nodeSetValue();
}if (n.length == 0) {return new StringValue(‘‘);
} else {return new StringValue(n[0].nodeName);
}
},‘string‘: function(ctx) {
assert(this.args.length == 1 || this.args.length == 0);if (this.args.length == 0) {return new StringValue(new NodeSetValue([ ctx.node ]).stringValue());
} else {return new StringValue(this.args[0].evaluate(ctx).stringValue());
}
},‘concat‘: function(ctx) {
var ret = ‘‘;for (var i = 0; i < this.args.length; ++i) {
ret += this.args[i].evaluate(ctx).stringValue();
}return new StringValue(ret);
},‘starts-with‘: function(ctx) {
assert(this.args.length == 2);
var s0 = this.args[0].evaluate(ctx).stringValue();
var s1 = this.args[1].evaluate(ctx).stringValue();return new BooleanValue(s0.indexOf(s1) == 0);
},‘contains‘: function(ctx) {
assert(this.args.length == 2);
var s0 = this.args[0].evaluate(ctx).stringValue();
var s1 = this.args[1].evaluate(ctx).stringValue();return new BooleanValue(s0.indexOf(s1) != -1);
},‘substring-before‘: function(ctx) {
assert(this.args.length == 2);
var s0 = this.args[0].evaluate(ctx).stringValue();
var s1 = this.args[1].evaluate(ctx).stringValue();
var i = s0.indexOf(s1);
var ret;if (i == -1) {
ret = ‘‘;
} else {
ret = s0.substr(0,i);
}return new StringValue(ret);
},‘substring-after‘: function(ctx) {
assert(this.args.length == 2);
var s0 = this.args[0].evaluate(ctx).stringValue();
var s1 = this.args[1].evaluate(ctx).stringValue();
var i = s0.indexOf(s1);
var ret;if (i == -1) {
ret = ‘‘;
} else {
ret = s0.substr(i + s1.length);
}return new StringValue(ret);
},‘substring‘: function(ctx) {// NOTE: XPath defines the position of the first character in a// string to be 1, in JavaScript this is 0 ([XPATH] Section 4.2).assert(this.args.length == 2 || this.args.length == 3);
var s0 = this.args[0].evaluate(ctx).stringValue();
var s1 = this.args[1].evaluate(ctx).numberValue();
var ret;if (this.args.length == 2) {
var i1 = Math.max(0, Math.round(s1) - 1);
ret = s0.substr(i1);
} else {
var s2 = this.args[2].evaluate(ctx).numberValue();
var i0 = Math.round(s1) - 1;
var i1 = Math.max(0, i0);
var i2 = Math.round(s2) - Math.max(0, -i0);
ret = s0.substr(i1, i2);
}return new StringValue(ret);
},‘string-length‘: function(ctx) {
var s;if (this.args.length > 0) {
s = this.args[0].evaluate(ctx).stringValue();
} els#
|
