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This documentation is no longer maintained.
/**
* Provides the language utilites and extensions used by the library
* @class YAHOO.lang
*/
YAHOO.lang = YAHOO.lang || {};
(function() {
var L = YAHOO.lang,
OP = Object.prototype,
ARRAY_TOSTRING = '[object Array]',
FUNCTION_TOSTRING = '[object Function]',
OBJECT_TOSTRING = '[object Object]',
NOTHING = [],
HTML_CHARS = {
'&': '&',
'<': '<',
'>': '>',
'"': '"',
"'": ''',
'/': '/',
'`': '`'
},
// ADD = ["toString", "valueOf", "hasOwnProperty"],
ADD = ["toString", "valueOf"],
OB = {
/**
* Determines wheather or not the provided object is an array.
* @method isArray
* @param {any} o The object being testing
* @return {boolean} the result
*/
isArray: function(o) {
return OP.toString.apply(o) === ARRAY_TOSTRING;
},
/**
* Determines whether or not the provided object is a boolean
* @method isBoolean
* @param {any} o The object being testing
* @return {boolean} the result
*/
isBoolean: function(o) {
return typeof o === 'boolean';
},
/**
* Determines whether or not the provided object is a function.
* Note: Internet Explorer thinks certain functions are objects:
*
* var obj = document.createElement("object");
* YAHOO.lang.isFunction(obj.getAttribute) // reports false in IE
*
* var input = document.createElement("input"); // append to body
* YAHOO.lang.isFunction(input.focus) // reports false in IE
*
* You will have to implement additional tests if these functions
* matter to you.
*
* @method isFunction
* @param {any} o The object being testing
* @return {boolean} the result
*/
isFunction: function(o) {
return (typeof o === 'function') || OP.toString.apply(o) === FUNCTION_TOSTRING;
},
/**
* Determines whether or not the provided object is null
* @method isNull
* @param {any} o The object being testing
* @return {boolean} the result
*/
isNull: function(o) {
return o === null;
},
/**
* Determines whether or not the provided object is a legal number
* @method isNumber
* @param {any} o The object being testing
* @return {boolean} the result
*/
isNumber: function(o) {
return typeof o === 'number' && isFinite(o);
},
/**
* Determines whether or not the provided object is of type object
* or function
* @method isObject
* @param {any} o The object being testing
* @return {boolean} the result
*/
isObject: function(o) {
return (o && (typeof o === 'object' || L.isFunction(o))) || false;
},
/**
* Determines whether or not the provided object is a string
* @method isString
* @param {any} o The object being testing
* @return {boolean} the result
*/
isString: function(o) {
return typeof o === 'string';
},
/**
* Determines whether or not the provided object is undefined
* @method isUndefined
* @param {any} o The object being testing
* @return {boolean} the result
*/
isUndefined: function(o) {
return typeof o === 'undefined';
},
/**
* IE will not enumerate native functions in a derived object even if the
* function was overridden. This is a workaround for specific functions
* we care about on the Object prototype.
* @property _IEEnumFix
* @param {Function} r the object to receive the augmentation
* @param {Function} s the object that supplies the properties to augment
* @static
* @private
*/
_IEEnumFix: (YAHOO.env.ua.ie) ? function(r, s) {
var i, fname, f;
for (i=0;i<ADD.length;i=i+1) {
fname = ADD[i];
f = s[fname];
if (L.isFunction(f) && f!=OP[fname]) {
r[fname]=f;
}
}
} : function(){},
/**
* <p>
* Returns a copy of the specified string with special HTML characters
* escaped. The following characters will be converted to their
* corresponding character entities:
* <code>& < > " ' / `</code>
* </p>
*
* <p>
* This implementation is based on the
* <a href="http://www.owasp.org/index.php/XSS_(Cross_Site_Scripting)_Prevention_Cheat_Sheet">OWASP
* HTML escaping recommendations</a>. In addition to the characters
* in the OWASP recommendation, we also escape the <code>`</code>
* character, since IE interprets it as an attribute delimiter when used in
* innerHTML.
* </p>
*
* @method escapeHTML
* @param {String} html String to escape.
* @return {String} Escaped string.
* @static
* @since 2.9.0
*/
escapeHTML: function (html) {
return html.replace(/[&<>"'\/`]/g, function (match) {
return HTML_CHARS[match];
});
},
/**
* Utility to set up the prototype, constructor and superclass properties to
* support an inheritance strategy that can chain constructors and methods.
* Static members will not be inherited.
*
* @method extend
* @static
* @param {Function} subc the object to modify
* @param {Function} superc the object to inherit
* @param {Object} overrides additional properties/methods to add to the
* subclass prototype. These will override the
* matching items obtained from the superclass
* if present.
*/
extend: function(subc, superc, overrides) {
if (!superc||!subc) {
throw new Error("extend failed, please check that " +
"all dependencies are included.");
}
var F = function() {}, i;
F.prototype=superc.prototype;
subc.prototype=new F();
subc.prototype.constructor=subc;
subc.superclass=superc.prototype;
if (superc.prototype.constructor == OP.constructor) {
superc.prototype.constructor=superc;
}
if (overrides) {
for (i in overrides) {
if (L.hasOwnProperty(overrides, i)) {
subc.prototype[i]=overrides[i];
}
}
L._IEEnumFix(subc.prototype, overrides);
}
},
/**
* Applies all properties in the supplier to the receiver if the
* receiver does not have these properties yet. Optionally, one or
* more methods/properties can be specified (as additional
* parameters). This option will overwrite the property if receiver
* has it already. If true is passed as the third parameter, all
* properties will be applied and _will_ overwrite properties in
* the receiver.
*
* @method augmentObject
* @static
* @since 2.3.0
* @param {Function} r the object to receive the augmentation
* @param {Function} s the object that supplies the properties to augment
* @param {String*|boolean} arguments zero or more properties methods
* to augment the receiver with. If none specified, everything
* in the supplier will be used unless it would
* overwrite an existing property in the receiver. If true
* is specified as the third parameter, all properties will
* be applied and will overwrite an existing property in
* the receiver
*/
augmentObject: function(r, s) {
if (!s||!r) {
throw new Error("Absorb failed, verify dependencies.");
}
var a=arguments, i, p, overrideList=a[2];
if (overrideList && overrideList!==true) { // only absorb the specified properties
for (i=2; i<a.length; i=i+1) {
r[a[i]] = s[a[i]];
}
} else { // take everything, overwriting only if the third parameter is true
for (p in s) {
if (overrideList || !(p in r)) {
r[p] = s[p];
}
}
L._IEEnumFix(r, s);
}
return r;
},
/**
* Same as YAHOO.lang.augmentObject, except it only applies prototype properties
* @see YAHOO.lang.augmentObject
* @method augmentProto
* @static
* @param {Function} r the object to receive the augmentation
* @param {Function} s the object that supplies the properties to augment
* @param {String*|boolean} arguments zero or more properties methods
* to augment the receiver with. If none specified, everything
* in the supplier will be used unless it would overwrite an existing
* property in the receiver. if true is specified as the third
* parameter, all properties will be applied and will overwrite an
* existing property in the receiver
*/
augmentProto: function(r, s) {
if (!s||!r) {
throw new Error("Augment failed, verify dependencies.");
}
//var a=[].concat(arguments);
var a=[r.prototype,s.prototype], i;
for (i=2;i<arguments.length;i=i+1) {
a.push(arguments[i]);
}
L.augmentObject.apply(this, a);
return r;
},
/**
* Returns a simple string representation of the object or array.
* Other types of objects will be returned unprocessed. Arrays
* are expected to be indexed. Use object notation for
* associative arrays.
* @method dump
* @since 2.3.0
* @param o {Object} The object to dump
* @param d {int} How deep to recurse child objects, default 3
* @return {String} the dump result
*/
dump: function(o, d) {
var i,len,s=[],OBJ="{...}",FUN="f(){...}",
COMMA=', ', ARROW=' => ';
// Cast non-objects to string
// Skip dates because the std toString is what we want
// Skip HTMLElement-like objects because trying to dump
// an element will cause an unhandled exception in FF 2.x
if (!L.isObject(o)) {
return o + "";
} else if (o instanceof Date || ("nodeType" in o && "tagName" in o)) {
return o;
} else if (L.isFunction(o)) {
return FUN;
}
// dig into child objects the depth specifed. Default 3
d = (L.isNumber(d)) ? d : 3;
// arrays [1, 2, 3]
if (L.isArray(o)) {
s.push("[");
for (i=0,len=o.length;i<len;i=i+1) {
if (L.isObject(o[i])) {
s.push((d > 0) ? L.dump(o[i], d-1) : OBJ);
} else {
s.push(o[i]);
}
s.push(COMMA);
}
if (s.length > 1) {
s.pop();
}
s.push("]");
// objects {k1 => v1, k2 => v2}
} else {
s.push("{");
for (i in o) {
if (L.hasOwnProperty(o, i)) {
s.push(i + ARROW);
if (L.isObject(o[i])) {
s.push((d > 0) ? L.dump(o[i], d-1) : OBJ);
} else {
s.push(o[i]);
}
s.push(COMMA);
}
}
if (s.length > 1) {
s.pop();
}
s.push("}");
}
return s.join("");
},
/**
* Does variable substitution on a string. It scans through the string
* looking for expressions enclosed in { } braces. If an expression
* is found, it is used a key on the object. If there is a space in
* the key, the first word is used for the key and the rest is provided
* to an optional function to be used to programatically determine the
* value (the extra information might be used for this decision). If
* the value for the key in the object, or what is returned from the
* function has a string value, number value, or object value, it is
* substituted for the bracket expression and it repeats. If this
* value is an object, it uses the Object's toString() if this has
* been overridden, otherwise it does a shallow dump of the key/value
* pairs.
*
* By specifying the recurse option, the string is rescanned after
* every replacement, allowing for nested template substitutions.
* The side effect of this option is that curly braces in the
* replacement content must be encoded.
*
* @method substitute
* @since 2.3.0
* @param s {String} The string that will be modified.
* @param o {Object} An object containing the replacement values
* @param f {Function} An optional function that can be used to
* process each match. It receives the key,
* value, and any extra metadata included with
* the key inside of the braces.
* @param recurse {boolean} default true - if not false, the replaced
* string will be rescanned so that nested substitutions are possible.
* @return {String} the substituted string
*/
substitute: function (s, o, f, recurse) {
var i, j, k, key, v, meta, saved=[], token, lidx=s.length,
DUMP='dump', SPACE=' ', LBRACE='{', RBRACE='}',
dump, objstr;
for (;;) {
i = s.lastIndexOf(LBRACE, lidx);
if (i < 0) {
break;
}
j = s.indexOf(RBRACE, i);
if (i + 1 > j) {
break;
}
//Extract key and meta info
token = s.substring(i + 1, j);
key = token;
meta = null;
k = key.indexOf(SPACE);
if (k > -1) {
meta = key.substring(k + 1);
key = key.substring(0, k);
}
// lookup the value
v = o[key];
// if a substitution function was provided, execute it
if (f) {
v = f(key, v, meta);
}
if (L.isObject(v)) {
if (L.isArray(v)) {
v = L.dump(v, parseInt(meta, 10));
} else {
meta = meta || "";
// look for the keyword 'dump', if found force obj dump
dump = meta.indexOf(DUMP);
if (dump > -1) {
meta = meta.substring(4);
}
objstr = v.toString();
// use the toString if it is not the Object toString
// and the 'dump' meta info was not found
if (objstr === OBJECT_TOSTRING || dump > -1) {
v = L.dump(v, parseInt(meta, 10));
} else {
v = objstr;
}
}
} else if (!L.isString(v) && !L.isNumber(v)) {
// This {block} has no replace string. Save it for later.
v = "~-" + saved.length + "-~";
saved[saved.length] = token;
// break;
}
s = s.substring(0, i) + v + s.substring(j + 1);
if (recurse === false) {
lidx = i-1;
}
}
// restore saved {block}s
for (i=saved.length-1; i>=0; i=i-1) {
s = s.replace(new RegExp("~-" + i + "-~"), "{" + saved[i] + "}", "g");
}
return s;
},
/**
* Returns a string without any leading or trailing whitespace. If
* the input is not a string, the input will be returned untouched.
* @method trim
* @since 2.3.0
* @param s {string} the string to trim
* @return {string} the trimmed string
*/
trim: function(s){
try {
return s.replace(/^\s+|\s+$/g, "");
} catch(e) {
return s;
}
},
/**
* Returns a new object containing all of the properties of
* all the supplied objects. The properties from later objects
* will overwrite those in earlier objects.
* @method merge
* @since 2.3.0
* @param arguments {Object*} the objects to merge
* @return the new merged object
*/
merge: function() {
var o={}, a=arguments, l=a.length, i;
for (i=0; i<l; i=i+1) {
L.augmentObject(o, a[i], true);
}
return o;
},
/**
* Executes the supplied function in the context of the supplied
* object 'when' milliseconds later. Executes the function a
* single time unless periodic is set to true.
* @method later
* @since 2.4.0
* @param when {int} the number of milliseconds to wait until the fn
* is executed
* @param o the context object
* @param fn {Function|String} the function to execute or the name of
* the method in the 'o' object to execute
* @param data [Array] data that is provided to the function. This accepts
* either a single item or an array. If an array is provided, the
* function is executed with one parameter for each array item. If
* you need to pass a single array parameter, it needs to be wrapped in
* an array [myarray]
* @param periodic {boolean} if true, executes continuously at supplied
* interval until canceled
* @return a timer object. Call the cancel() method on this object to
* stop the timer.
*/
later: function(when, o, fn, data, periodic) {
when = when || 0;
o = o || {};
var m=fn, d=data, f, r;
if (L.isString(fn)) {
m = o[fn];
}
if (!m) {
throw new TypeError("method undefined");
}
if (!L.isUndefined(data) && !L.isArray(d)) {
d = [data];
}
f = function() {
m.apply(o, d || NOTHING);
};
r = (periodic) ? setInterval(f, when) : setTimeout(f, when);
return {
interval: periodic,
cancel: function() {
if (this.interval) {
clearInterval(r);
} else {
clearTimeout(r);
}
}
};
},
/**
* A convenience method for detecting a legitimate non-null value.
* Returns false for null/undefined/NaN, true for other values,
* including 0/false/''
* @method isValue
* @since 2.3.0
* @param o {any} the item to test
* @return {boolean} true if it is not null/undefined/NaN || false
*/
isValue: function(o) {
// return (o || o === false || o === 0 || o === ''); // Infinity fails
return (L.isObject(o) || L.isString(o) || L.isNumber(o) || L.isBoolean(o));
}
};
/**
* Determines whether or not the property was added
* to the object instance. Returns false if the property is not present
* in the object, or was inherited from the prototype.
* This abstraction is provided to enable hasOwnProperty for Safari 1.3.x.
* There is a discrepancy between YAHOO.lang.hasOwnProperty and
* Object.prototype.hasOwnProperty when the property is a primitive added to
* both the instance AND prototype with the same value:
* <pre>
* var A = function() {};
* A.prototype.foo = 'foo';
* var a = new A();
* a.foo = 'foo';
* alert(a.hasOwnProperty('foo')); // true
* alert(YAHOO.lang.hasOwnProperty(a, 'foo')); // false when using fallback
* </pre>
* @method hasOwnProperty
* @param {any} o The object being testing
* @param prop {string} the name of the property to test
* @return {boolean} the result
*/
L.hasOwnProperty = (OP.hasOwnProperty) ?
function(o, prop) {
return o && o.hasOwnProperty && o.hasOwnProperty(prop);
} : function(o, prop) {
return !L.isUndefined(o[prop]) &&
o.constructor.prototype[prop] !== o[prop];
};
// new lang wins
OB.augmentObject(L, OB, true);
/*
* An alias for <a href="YAHOO.lang.html">YAHOO.lang</a>
* @class YAHOO.util.Lang
*/
YAHOO.util.Lang = L;
/**
* Same as YAHOO.lang.augmentObject, except it only applies prototype
* properties. This is an alias for augmentProto.
* @see YAHOO.lang.augmentObject
* @method augment
* @static
* @param {Function} r the object to receive the augmentation
* @param {Function} s the object that supplies the properties to augment
* @param {String*|boolean} arguments zero or more properties methods to
* augment the receiver with. If none specified, everything
* in the supplier will be used unless it would
* overwrite an existing property in the receiver. if true
* is specified as the third parameter, all properties will
* be applied and will overwrite an existing property in
* the receiver
*/
L.augment = L.augmentProto;
/**
* An alias for <a href="YAHOO.lang.html#augment">YAHOO.lang.augment</a>
* @for YAHOO
* @method augment
* @static
* @param {Function} r the object to receive the augmentation
* @param {Function} s the object that supplies the properties to augment
* @param {String*} arguments zero or more properties methods to
* augment the receiver with. If none specified, everything
* in the supplier will be used unless it would
* overwrite an existing property in the receiver
*/
YAHOO.augment = L.augmentProto;
/**
* An alias for <a href="YAHOO.lang.html#extend">YAHOO.lang.extend</a>
* @method extend
* @static
* @param {Function} subc the object to modify
* @param {Function} superc the object to inherit
* @param {Object} overrides additional properties/methods to add to the
* subclass prototype. These will override the
* matching items obtained from the superclass if present.
*/
YAHOO.extend = L.extend;
})();