dtonhofer

dtonhofer

Functional Programming in Java, Second Edition: p 151 "func" instead of "memoizedFunction"

@venkats

At 2/3rd of the page, we read;

Within the computeMaxProfit() method, we perform our task, and when it’s time to recurse we route the call to func

func should be memoizedFunction, as used in the example code.

This will return quickly if the value has been cached or memoized.

Aren’t those two words equivalent? So just:

This will return quickly if the value has been cached.

But one may want to note at the start of this chapter that “cached” and “memoized”/“memoing” are synonyms (I would say)

P.S.

The example code uses alternatingly length and rodLength as name for the input parameter; this should be unified.

In this case then one could write:

    public int maxProfitMemoized(final int length) {
        BiFunction<Function<Integer, Integer>, Integer, Integer> biFunction = this::computeMaxProfit;
        return Memoizer.callMemoized(biFunction, length);
    }

The above also emphasizes the fact that this::computeMaxProfit actually maps to BiFunction<Function<Integer, Integer>, Integer, Integer>, i.e. actually allows the compiler to create an anonymous implementation of BiFunction<Function<Integer, Integer>, Integer, Integer> that calls this::computeMaxProfit, something that is not entirely self-evident.

P.P.S.

In an article by David S. Warren, “Memoing for Logic Programs”, the following reference for “memoing” is given:

“Memo” Functions and Machine Learning

https://www.nature.com/articles/218019a0

Marked As Solved

venkats

venkats

Author of Programming Kotlin, Rediscovering JavaScript (and 6 other titles)

Addressed the suggestions for parameter name and also reference to func. Thank you.

Also Liked

venkats

venkats

Author of Programming Kotlin, Rediscovering JavaScript (and 6 other titles)

Thank you, David. I really appreciate the suggestions and will review them and address as necessary. Thank you so much for your time and attention to these details.

Where Next?

Popular Pragmatic Bookshelf topics Top

New
brianokken
Many tasks_proj/tests directories exist in chapters 2, 3, 5 that have tests that use the custom markers smoke and get, which are not decl...
New
johnp
Hi Brian, Looks like the api for tinydb has changed a little. Noticed while working on chapter 7 that the .purge() call to the db throws...
New
edruder
I thought that there might be interest in using the book with Rails 6.1 and Ruby 2.7.2. I’ll note what I needed to do differently here. ...
New
jdufour
Hello! On page xix of the preface, it says there is a community forum "… for help if your’re stuck on one of the exercises in this book… ...
New
JohnS
I can’t setup the Rails source code. This happens in a working directory containing multiple (postgres) Rails apps. With: ruby-3.0.0 s...
New
New
brian-m-ops
#book-python-testing-with-pytest-second-edition Hi. Thanks for writing the book. I am just learning so this might just of been an issue ...
New
New
rainforest
Hi, I’ve got a question about the implementation of PubSub when using a Phoenix.Socket.Transport behaviour rather than channels. Before ...
New

Other popular topics Top

PragmaticBookshelf
Ruby, Io, Prolog, Scala, Erlang, Clojure, Haskell. With Seven Languages in Seven Weeks, by Bruce A. Tate, you’ll go beyond the syntax—and...
New
Rainer
My first contact with Erlang was about 2 years ago when I used RabbitMQ, which is written in Erlang, for my job. This made me curious and...
New
mafinar
Crystal recently reached version 1. I had been following it for awhile but never got to really learn it. Most languages I picked up out o...
New
AstonJ
Continuing the discussion from Thinking about learning Crystal, let’s discuss - I was wondering which languages don’t GC - maybe we can c...
New
PragmaticBookshelf
Use WebRTC to build web applications that stream media and data in real time directly from one user to another, all in the browser. ...
New
mafinar
This is going to be a long an frequently posted thread. While talking to a friend of mine who has taken data structure and algorithm cou...
New
New
First poster: AstonJ
Jan | Rethink the Computer. Jan turns your computer into an AI machine by running LLMs locally on your computer. It’s a privacy-focus, l...
New
NewsBot
Node.js v22.14.0 has been released. Link: Release 2025-02-11, Version 22.14.0 'Jod' (LTS), @aduh95 · nodejs/node · GitHub
New
Fl4m3Ph03n1x
Background Lately I am in a quest to find a good quality TTS ai generation tool to run locally in order to create audio for some videos I...
New

Latest in Functional Programming in Java, Second Edition

Functional Programming in Java, Second Edition Portal

Sub Categories: