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simplify javascript if statement where conditions are identical except for variable

I apologize if this is a duplicate question. It's such a use-case question that it seems everyone has their own version.
I'm wondering if this can be simplified:
if ($('.taxclass').text().indexOf(tax1)>-1 || $('.taxclass').text().indexOf(tax2)>-1) {}

It's pretty simple as it stands, but you could make it a bit less redundant mainly by getting the elements text only once and reusing the variable:
var text = $('.taxclass').text();
if (text.indexOf(tax1)>-1 || text.indexOf(tax2)>-1) {
}
A further note could be to reduce the traversal of the DOM by using an identifier and looking only for a distinct element (if that suits your needs) instead of every possible thing that has the class taxclass.

var txt = $('.taxclass').text();
if (txt.indexOf(tax1)>-1 || txt.indexOf(tax2)>-1) {}

One super quick way would be not to duplicate $('.taxclass').text()
Try something like
var tax = $('.taxclass').text();
if (tax.indexOf(tax1)>-1 || tax.indexOf(tax2)>-1) {}

You can store $('.taxclass').text() in a variable, or use regex.
var str = $('.taxclass').text();
if (str.indexOf(tax1) > -1 || str.indexOf(tax2) > -1)
// Or with regex
if(/(text1)|(text2)/.test($('.taxclass').text())
{}

Quick and dirty:
text.indexOf(tax1+"~"+tax2)>-1
Functional, works on n strings, but verbose:
[tax1, tax2].some(function(s) { return s.indexOf(text)>-1 })
As a prototype:
String.prototype.foundIn = function() {
var s=this; return Array.prototype.slice.call(arguments).some(function(m)
{return m.indexOf(s)>-1});
};
Usage:
$('.taxclass').text().foundIn(tax1, tax2)

What about:
f = function (x) { return $('.taxclass').text().indexOf(x) > -1; }
if (f(tax1) || f(tax2)) {}

Jasmine expect logic (expect A OR B)

I need to set the test to succeed if one of the two expectations is met:
expect(mySpy.mostRecentCall.args[0]).toEqual(jasmine.any(Number));
expect(mySpy.mostRecentCall.args[0]).toEqual(false);
I expected it to look like this:
expect(mySpy.mostRecentCall.args[0]).toEqual(jasmine.any(Number)).or.toEqual(false);
Is there anything I missed in the docs or do I have to write my own matcher?

Add multiple comparable strings into an array and then compare. Reverse the order of comparison.
expect(["New", "In Progress"]).toContain(Status);

This is an old question, but in case anyone is still looking I have another answer.
How about building the logical OR expression and just expecting that? Like this:
var argIsANumber = !isNaN(mySpy.mostRecentCall.args[0]);
var argIsBooleanFalse = (mySpy.mostRecentCall.args[0] === false);
expect( argIsANumber || argIsBooleanFalse ).toBe(true);
This way, you can explicitly test/expect the OR condition, and you just need to use Jasmine to test for a Boolean match/mismatch. Will work in Jasmine 1 or Jasmine 2 :)

Note: This solution contains syntax for versions prior to Jasmine v2.0.
For more information on custom matchers now, see: https://jasmine.github.io/2.0/custom_matcher.html
Matchers.js works with a single 'result modifier' only - not:
core/Spec.js:
jasmine.Spec.prototype.expect = function(actual) {
var positive = new (this.getMatchersClass_())(this.env, actual, this);
positive.not = new (this.getMatchersClass_())(this.env, actual, this, true);
return positive;
core/Matchers.js:
jasmine.Matchers = function(env, actual, spec, opt_isNot) {
...
this.isNot = opt_isNot || false;
}
...
jasmine.Matchers.matcherFn_ = function(matcherName, matcherFunction) {
return function() {
...
if (this.isNot) {
result = !result;
}
}
}
So it looks like you indeed need to write your own matcher (from within a before or it bloc for correct this). For example:
this.addMatchers({
toBeAnyOf: function(expecteds) {
var result = false;
for (var i = 0, l = expecteds.length; i < l; i++) {
if (this.actual === expecteds[i]) {
result = true;
break;
}
}
return result;
}
});

You can take the comparison out of the expect statement to gain full use of comparison operators.
let expectResult = (typeof(await varA) == "number" || typeof(await varA) == "object" );
expect (expectResult).toBe(true);

JavaScript/jQuery equivalent of LINQ Any()

Is there an equivalent of IEnumerable.Any(Predicate<T>) in JavaScript or jQuery?
I am validating a list of items, and want to break early if error is detected. I could do it using $.each, but I need to use an external flag to see if the item was actually found:
var found = false;
$.each(array, function(i) {
if (notValid(array[i])) {
found = true;
}
return !found;
});
What would be a better way? I don't like using plain for with JavaScript arrays because it iterates over all of its members, not just values.

These days you could actually use Array.prototype.some (specced in ES5) to get the same effect:
array.some(function(item) {
return notValid(item);
});

You could use variant of jQuery is function which accepts a predicate:
$(array).is(function(index) {
return notValid(this);
});

Xion's answer is correct. To expand upon his answer:
jQuery's .is(function) has the same behavior as .NET's IEnumerable.Any(Predicate<T>).
From http://docs.jquery.com/is:
Checks the current selection against an expression and returns true, if at least one element of the selection fits the given expression.

You should use an ordinary for loop (not for ... in), which will only loop through array elements.

You might use array.filter (IE 9+ see link below for more detail)
[].filter(function(){ return true|false ;}).length > 0;
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/filter

I would suggest that you try the JavaScript for in loop. However, be aware that the syntax is quite different than what you get with a .net IEnumerable. Here is a small illustrative code sample.
var names = ['Alice','Bob','Charlie','David'];
for (x in names)
{
var name = names[x];
alert('Hello, ' + name);
}
var cards = { HoleCard: 'Ace of Spades', VisibleCard='Five of Hearts' };
for (x in cards)
{
var position = x;
var card = card[x];
alert('I have a card: ' + position + ': ' + card);
}

I suggest you to use the $.grep() method. It's very close to IEnumerable.Any(Predicate<T>):
$.grep(array, function(n, i) {
return (n == 5);
});
Here a working sample to you: http://jsfiddle.net/ErickPetru/BYjcu/.
2021 Update
This answer was posted more than 10 years ago, so it's important to highlight that:
When it was published, it was a solution that made total sense, since there was nothing native to JavaScript to solve this problem with a single function call at that time;
The original question has the jQuery tag, so a jQuery-based answer is not only expected, it's a must. Down voting because of that doesn't makes sense at all.
JavaScript world evolved a lot since then, so if you aren't stuck with jQuery, please use a more updated solution! This one is here for historical purposes, and to be kept as reference for old needs that maybe someone still find useful when working with legacy code.

Necromancing.
If you cannot use array.some, you can create your own function in TypeScript:
interface selectorCallback_t<TSource>
{
(item: TSource): boolean;
}
function Any<TSource>(source: TSource[], predicate: selectorCallback_t<TSource> )
{
if (source == null)
throw new Error("ArgumentNullException: source");
if (predicate == null)
throw new Error("ArgumentNullException: predicate");
for (let i = 0; i < source.length; ++i)
{
if (predicate(source[i]))
return true;
}
return false;
} // End Function Any
Which transpiles down to
function Any(source, predicate)
{
if (source == null)
throw new Error("ArgumentNullException: source");
if (predicate == null)
throw new Error("ArgumentNullException: predicate");
for (var i = 0; i < source.length; ++i)
{
if (predicate(source[i]))
return true;
}
return false;
}
Usage:
var names = ['Alice','Bob','Charlie','David'];
Any(names, x => x === 'Alice');

Help refactor a small piece of Javascript code which identifies user's referrer source

I've written the following small piece of javascript (Based on the excellent parseURI function) to identify where the user originated from. I am new to Javascript, and although the code below works, was wondering if there is a more efficient method of achieving this same result?
try {
var path = parseUri(window.location).path;
var host = parseUri(document.referrer).host;
if (host == '') {
alert('no referrer');
}
else if (host.search(/google/) != -1 || host.search(/bing/) != -1 || host.search(/yahoo/) != -1) {
alert('Search Engine');
}
else {
alert('other');
}
}
catch(err) {}

You can simplify the host check using alternative searches:
else if (host.search(/google|bing|yahoo/) != -1 {
I'd also be tempted to test document referrer before extracting the host for your "no referrer" error.
(I've not tested this).

I end up defining a function called set in a lot of my projects. It looks like this:
function set() {
var result = {};
for (var i = 0; i < arguments.length; i++)
result[arguments[i]] = true;
return result;
}
Once you've got the portion of the hostname that you're looking for...
// low-fi way to grab the domain name without a regex; this assumes that the
// value before the final "." is the name that you want, so this doesn't work
// with .co.uk domains, for example
var domain = parseUri(document.referrer).host.split(".").slice(-2, 1)[0];
...you can elegantly test your result against a list using JavaScript's in operator and the set function we defined above:
if (domain in set("google", "bing", "yahoo"))
// do stuff
More info:
http://laurens.vd.oever.nl/weblog/items2005/setsinjavascript/

Ways to improve performance of this javascript code?

Don't be frightened, its a very basic code.
Just wanted to check with you guys if you know any methods to make it faster ? (still learning)
It looks so ugly :)
Or, if you notice anything which could be made differently... Thanks!
function pic_form_function(form, nr, val) {
document.getElementById("image_to_delete").value=0;
var re = /\..+$/;
var extension = val.match(re);
if (extension==".jpg" || extension==".jpeg" || extension==".gif" || extension==".png" || extension==".bmp") {
if (nr==1){
var ID_file1 = document.getElementById("pic_id_nr1").value;
window.parent.document.getElementById("pic1_filename").value=ID_file1+extension;
window.parent.document.getElementById("annonsera_nr_pics").value=1;
window.parent.document.getElementById("iframe_upload_pic").style.height="180px";
document.getElementById("pic_target").style.height="160px";
document.getElementById("pic_target").style.display="block";
document.getElementById("remove_pic").value=0;
document.getElementById("extra_pic_checkbox").style.display="inline";
document.getElementById("extra_pic_fnt").style.display="inline";
}
else if (nr==2){
var ID_file2 = document.getElementById("pic_id_nr2").value;
window.parent.document.getElementById("pic2_filename").value=ID_file2+extension; //Passing fileInputName to parent window...
window.parent.document.getElementById("annonsera_nr_pics").value=2;
document.getElementById("extrapic").value=2;
document.getElementById("pic_file3").disabled=false;
}
else if (nr==3){
var ID_file3 = document.getElementById("pic_id_nr3").value;
window.parent.document.getElementById("annonsera_nr_pics").value=3;
window.parent.document.getElementById("pic3_filename").value=ID_file3+extension;
document.getElementById("extrapic").value=3;
document.getElementById("pic_file4").disabled=false;
}
else if (nr==4){
var ID_file4 = document.getElementById("pic_id_nr4").value;
window.parent.document.getElementById("annonsera_nr_pics").value=4;
window.parent.document.getElementById("pic4_filename").value=ID_file4+extension;
document.getElementById("extrapic").value=4;
document.getElementById("pic_file5").disabled=false;
}
else if (nr==5){
var ID_file5 = document.getElementById("pic_id_nr5").value;
window.parent.document.getElementById("annonsera_nr_pics").value=5;
window.parent.document.getElementById("pic5_filename").value=ID_file5+extension;
document.getElementById("extrapic").value=5;
}
}
if (extension!=".jpg" && extension!=".jpeg" && extension!=".gif" && extension!=".png" && extension!=".bmp") {
window.parent.document.getElementById("annonsera_imagenotvalid_error").style.display="block";
}
else {
window.parent.document.getElementById("annonsera_imagenotvalid_error").style.display="none";
form.submit();
}
}

If me, I will define following on the top.
$=function(x){return document.getElementById(x);}
will replace all the document.getElementById to $ first.
or better user jQuery.

About performance:
To extract the file extension you can use the String.substring method instead of a RegExp, the performance improvement would be negligible but I think it gains readability:
var extension = val.substring(val.lastIndexOf('.'));
About the code:
You could have only one ID_file variable declared at the top of your function, and use it in the if blocks.
The else if blocks where nr==2, 3, and 4 are really similar, and you could do the same for those three cases:
//..
else if (nr >= 2 && nr <= 4){
ID_file = document.getElementById("pic_id_nr"+nr).value; // point #1 assumed
window.parent.document.getElementById("pic"+nr+"_filename").value=ID_file+extension;
window.parent.document.getElementById("annonsera_nr_pics").value = nr;
document.getElementById("extrapic").value = nr;
document.getElementById("pic_file"+(+nr+1)).disabled=false;
}
About readability:
You could define shorthands to common and verbose function calls at the beginning as S.Mark also suggests:
var el = document.getElementById,
parentEl = window.parent.document.getElementById;

Continuing what CMS did with code repetition, you can refactor the common code outside the sequence of else if blocks.
The switch statement was made to replace a sequence of ifs.
Instead of the above two suggestions, you could define functions do to the same tasks for a more readable implementation.
If you continue to use regexps (I personally find them very readable), remember that match returns an array.
Also, the .+ will greedily match all characters after the first period. Better to only match non-periods with [^.]+.
Instead of the long sequence of string comparisons, you can use objects as associative arrays:
var imageExtensions = {'.jpg': 1, '.jpeg': 1, '.gif': 1, '.png': 1, '.bmp': 1};
if (imageExtensions[extension]) {
The last if ... else ... is unnecessary, considering that the condition checks for the negation of the condition in the first if. Just move the else block to the end of the first if and turn the last if (...) to an else.
Personally, I find short error handling code more readable when placed next to the if statement that detected the error, rather than after a long block handling the non-error case. After the previous refactor, let's swap the if block with the else block and negate the conditional.
Taking all the above together, we get:
function pic_form_function(form, nr, val) {
document.getElementById("image_to_delete").value=0;
var extension = val.match(/\.[^.]+$/);
if (extension) {
extension = extension[0];
}
var imageExtensions = {'.jpg': 1, '.jpeg': 1, '.gif': 1, '.png': 1, '.bmp': 1};
if (! imageExtensions[extension]) {
window.parent.document.getElementById("annonsera_imagenotvalid_error").style.display="block";
} else {
var ID_file = document.getElementById("pic_id_nr" + nr).value;
window.parent.document.getElementById("pic"+nr+"_filename").value=ID_file+extension;
window.parent.document.getElementById("annonsera_nr_pics").value=nr;
switch (nr) {
case 1:
window.parent.document.getElementById("iframe_upload_pic").style.height="180px";
document.getElementById("pic_target").style.height="160px";
document.getElementById("pic_target").style.display="block";
document.getElementById("remove_pic").value=0;
document.getElementById("extra_pic_checkbox").style.display="inline";
document.getElementById("extra_pic_fnt").style.display="inline";
break;
case 2: // FALLTHRU
case 3: // FALLTHRU
case 4:
document.getElementById("pic_file"+nr).disabled=false;
// FALLTHRU
case 5:
document.getElementById("extrapic").value=nr;
break;
}
window.parent.document.getElementById("annonsera_imagenotvalid_error").style.display="none";
form.submit();
}
}
which is shorter, but could be more readable.
Note that if the $ wrapper is defined in 'window.parent', you should be able to call it as window.parent.$ in the child:
window.parent.$("annonsera_imagenotvalid_error").style.display="none";

There isn't any special computation being done beside traversing elements and assigning their attributes some values. So the code is not performing much to try to improve its performance.
On the other hand, you should use a library like jQuery for the kind of work you are doing. You might be able to cut short many traversals because you can have jQuery reuse the object it found and continue further from this point to look for other objects...

You should cache your dom lookups e.g.
var pic_target = document.getElementById("pic_target");
You can then use this variable to to apply the style and it only does the dom lookup once. I think this is a key thing to speeding up the js