a place to learn javascript for today's world.

Patterns with Objects

  • iterating over Object with for in loop

    let myObj = { "one" : 1, "two" : 2, "three" : 3 };
    let newArray = [];
    for (let int in myObj){
    newArray.push( int * 5);
    }
    // newArray now contains: [5, 10, 15]
    
  • iterating over Objects with array methods

    let myObj = { "one" : 1, "two" : 2, "three" : 3 };
    let newArray = Object.keys(myObj).map( key => 5 * myObj[key] );
    // newArray: [5, 10, 15];
    
  • cloning an object (shallow clone)

    const clone = {...original}
    
  • immutably add another prop to original

    const newobj = {...original, prop: newOne}