Example 1: javascript for loop
var colors=["red","blue","green"];
for (let i = 0; i < colors.length; i++) {
console.log(colors[i]);
}
Example 2: range javascript
[...Array(5).keys()];
=> [0, 1, 2, 3, 4]
Example 3: javascript for loops
JavaScript For Loop: Summary
There are three types of for loops: the regular for loop, the for/in loop and for/of loop.
The for loop iterates through an array.
The for/in loop iterates through the properties of an object.
The for/of loop iterates through iterable objects, like arrays and strings.
Example 4: javascript create range with a loop
function createRange(min, max) {
var range = [];
for (let i = min; i <= max; i++) {
range.push(i);
}
return range;
}
createRange(1, 5)
Example 5: javascript range
function range(start, stop, step = 1, circularFill = false, map = (value) => value) {
if (typeof stop === 'undefined') {
stop = start;
start = 0;
}
if (step > 0 && start >= stop) {
step = -step;
}
if (step < 0 && start <= stop) {
return [];
}
let index = start;
const result = [];
if (circularFill) {
const size = start + stop;
for (index; step > 0 ? index < size : index > size; index += step) {
result.push(map(index % stop));
}
return result;
}
for (index; step > 0 ? index < stop : index > stop; index += step) {
result.push(map(index));
}
return result;
}
range(8)
range(-8)
range(25, 30, 2);
range(-25, -30, -2);
range(5, 10, 1, true)
range(-5, -10, -1, true)
function rangeChars(text, start, stop, step, circularFill, map = (value) => value) {
start = text.indexOf(start);
stop = text.indexOf(stop) + 1;
return range(start, stop, step, circularFill, (i) => {
return map(text[i]);
});
}
rangeChars('shooooouuut!!!!', 'o', '!');
Example 6: for in range javascript
function* range(start=0, end=null, step=1) {
if (end == null) {
end = start;
start = 0;
}
for (let i=start; i < end; i+=step) {
yield i;
}
}