This is more out of curiosity but is it possible to concatenate comparisons in javascript?
example:
var foo = 'a',
bar = 'b';
if (foo === ('a' || bar)) {
console.log('yey');
}
as oposed to...
var foo = 'a',
bar = 'b';
if (foo === 'a' || foo === bar)) {
console.log('yey');
}
P.S: When you are comparing the same variable in several conditions, this could be very useful.
You can use Array.indexOf:
if (["a", "b"].indexOf(foo) > -1) {
console.log("yey");
}
Though this method is not supported by some old browsers, have a look at the compatibility issues in MDN -- there is an easy shim provided.
Another way, suggested by @Pointy in the comments, is to check if property exists in object:
if (foo in {a: 1, b: 1}) { // or {a: 1, b: 1}[foo]
console.log("yey");
}
There are several different ways to do this. My favorite is using an array in conjunction with indexOf.
if ( ['a', 'b'].indexOf(foo) > -1 ) {
console.log('yey');
}
The Array indexOf is one solution
Another option is a switch statement
switch (foo) {
case "a":
case "b":
console.log("bar");
break;
case "c":
console.log("SEE");
break;
default:
console.log("ELSE");
}
other solutions can also be an object look up or a regular expression.
Typically I'd use a regex for this:
if (^/a|b$/i.test(foo)) {
...
}
