A previous post discussed some basic array properties. This one drills down a little into the syntax for Ruby.
Making an Array
Arrays can be initialized with square brackets ([ ]). This is called a literal initialization. Its values are separated by commas and their index begins at zero.
[“dog”, “bird”, “cat”]
Dog is at index 0, bird is at index 1, etc.
You can access what is at a specific index number just by using that number.
pets = ["dog", "cat", "bird"]
=> ["dog", "cat", "bird"]
You can also assign elements to a specific index number, and the array will grow to accommodate. Index numbers with no content are “nil.”
pets = "hamster"
=> ["dog", "cat", "bird", nil, "hamster"]
- .first and .last will show you the first or last element
- .length will tell you how many elements there are
- .include[x] will tell you if x is included in the array (true or false)
- .find_index(x) will tell you at what index x is located
- .push adds to the end of an array
- .pop pops an element off the end
- .shift adds to the beginning of an array
- << does the same thing as push; it’s referred to as “shovel”
To convert the elements in an array into a string:
[“d”, “o”, “g”].join
To convert elements in an array into a string but separate them by something, like a hyphen:
[“d”, “o”, “g”].join(“-”)