My listing of action codes is here (and it’s a link at the top of every aTbRef page.
A list of dot-operators is here, but note many are alternatives of older versions, e.g.
So why the difference? Chaining makes the process more understandable. Less say the to get the output you want, you need to apply
function3() in that order to note “Some Note”:
$AnAttribute = function3(function2(function1("Some Note")));
The same, as chained dot operators:
$AnAttribute = "Some Note".function1().function2().function3();
In the first case you have to read from inside outwards to work out the process. In the latter case you read from left to write.
Note: not all action code operators can be used as dot-operators, see the above links for more.