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JavaScript

Posted by Dan Oswalt
Dan Oswalt
23,438 Points

JS equivalent of Python's easy way of cycling through iterables....

In Python, it's fantastically easy to search for a match by cycling through things in anything that's iterable:

if letter in 'abcdef':
    print(letter)

if item in itemlist:
    print(item)

In plain JS, is there a standard pattern for looking for a match that is less verbose than something like:

for(var index = 0; index <= list.length; i += 1) {
    if(list[index] === item) {
        console.log(item);
        break;
    }
}

?

2 Answers

Michael Hulet
Michael Hulet
47,842 Points
Michael Hulet
Michael Hulet
47,842 Points

You could use the indexOf method to do that. If it returns -1, it isn't in the list. Otherwise, it tells you where in the list it is. This should work:

if(array.indexOf(thing) >= 0){
    // It's in the array
}
else{
    // It's not in the array
}
Dan Oswalt
Dan Oswalt
23,438 Points
Dan Oswalt
Dan Oswalt
23,438 Points

Oh right, thank you, knew there was a better way.