Ninja Mate

let a='man'
()=>{
    let b='hi'
    console.log(b)//hi 
    console.log(a)//man
}
    console.log(b)//Uncaught ReferenceError: b is not defined

"use strict";
const HideKeyboard=()=> {
    //this set timeout
    setTimeout(function() {
        var field = document.createElement('input');
        field.setAttribute('type', 'text');
        field.setAttribute('style', 'position:absolute; top: 0px; -webkit-transform: translateY(-9999px); -webkit-user-modify: read-write-plaintext-only; left:0px;');
        document.body.appendChild(field);

        field.onfocus = function(){
            setTimeout(function() {
                field.setAttribute('style', 'display:none;');
                setTimeout(function() {
                    document.body.removeChild(field);
                    document.body.focus();
                }, 14);
            }, 200);
        };
        field.focus();
    }, 50);
};

export default HideKeyboard;

onChange={ (event)=> {
    var comment = that.state.comments;
    comment[index] = event.target.value;
    that.setState({ comments: comment });
}}