function doubleSay (str) {
return str + ", " + str;
}
function capitalize (str) {
return str[0].toUpperCase() + str.substring(1);
}
function exclaim (str) {
return str + '!';
}
...the following invocations are equivalent:
let result = exclaim(capitalize(doubleSay("hello")));
result //=> "Hello, hello!"
let result = "hello"
|> doubleSay
|> capitalize
|> exclaim;
result //=> "Hello, hello!"