April 2018
Intermediate to advanced
408 pages
10h 42m
English
A monad allows us to impose an order on an expression evaluation in an otherwise lenient language. We can use a monad to insist that an expression such as a + b + c is evaluated in left-to-right order. This can interfere with the compiler's ability to optimize expression evaluation. This is necessary, for example, when we want files to have their content read or written in a specific order: a monad assures that the read() and write() functions are evaluated in a particular order.
Languages that are lenient and have optimizing compilers benefit from monads imposing order on the evaluation of expressions. Python, for the most part, is strict and does not optimize. There are no practical requirements for monads.
However, ...