sometimes
i dream in code
class Book:
def __init__(self, a, t, p):
self.author = a
self.title = t
self.published = p
def description(self):
return self.title + " by " + self.author + " published in " + self.published
bits of programs
glide around
in my head
function Book (t, a, p) {
this.title = t;
this.author = a;
this.published = p;
this.description = function() {
return this.title + ' by ' + this.author + ' published in ' + this.published;
};
return this;
}
i close my eyes
and there it is
code
0900 Dim thisBook As book
always the code
pointy k's
and bumpy m's
it follows me
from one rem cycle
to the next
01 BOOK
05 TITLE PIC X(15).
05 AUTHOR PIC X(15).
05 YEARPUB PIC 9(4).
i've used
a lot of
programming languages
class Book {
private String title;
private String author;
private int year_published;
public Book(t, a, p) {
title = t;
author = a;
year_published = p;
}
public getDescription() {
return title + " by " + author + " published in " + year_published;
}
}
from BASIC to FORTRAN
0100 author = "Tolstoy"
0200 title = "War and Peace"
0300 published = 1869
to Ruby and Python
class Book
attr_accessor :author, :title, :published
def initialize(a, t, p)
@title = t;
@author = a;
@published = p;
end
def description
"#{@title} by #{@author} published in #{@published}"
end
end
sometimes
it all
runs together
0100 class Book:
0200 attr_accessor :author, :title, :published
0300
0400 public Book(t, a, p) {
0500 title = t;
0600 author = a;
0700 year_published = p;
0800 }
0900 end
these dreams
of code
they are hell
var codeBook = Book("Inferno", "Dante", 1320);
coding is my job
five days a week
i'm coding man
but i don’t want to code
when i'm sleeping
i just want to sleep
when i'm asleep
hell
pride = Book.new("Pride and Prejudice", "Austen", 1813)
since i can't
get away from the code
i try to make it
as easy as i can
after all
i’m tired
in fact i’m asleep
life should be easy
when i’m asleep
NOW = TIME(0)
CALL MAKEEASY(NOW)
sometimes
when i’m dreaming
in code
i make an array
pride = new Book("Pride and Prejudice", "Austen", 1813);
war = new Book("War and Peace", "Tolstoy", 1869);
books = [pride, war];
and i let your code
borrow my array
your_nefarious_code(books);
and your code
changes my array
// Your nefarious code.
public your_nefarious_code(Book[] books) {
zombies = new Book("Pride and Prejudice and Zombies", "Grahame-Smith", 2009);
books[0] = zombies;
}
it's my array
i didn't want you
to change it
truth be told
sometimes
i do it to myself
// An honest mistake
public my_function(Book[] books) {
jaws = new Book("Jaws", "Benchley", 1974);
books[0] = jaws;
}
i have an excuse though
i’m asleep
# Don't modify this code unless you are unconscious.
this changing
behind my back
makes me
thrash in my sleep
def []=(idx, value)
raise "YouCantChangeMyArraySucker"
end
so in my dream
i make
a new rule
no more
changing arrays
ever
// Your nefarious code foiled.
// Blam! Throws a YouCantChangeMyArraySuckerException!
books[0] = zombies;
once i create an array
that's it
you can’t change it
neither can i
your_impossible_to_be_nefarious_code(books);
now
i don’t
have to worry
about your code or threads
messing with my arrays
or my code
or my threads
it’s just easier
0600 REM I like zombies
but sometimes
i need
to change my array
GoTo 0000
but if i do
i’m back to square one
i don’t want to deal with it
function justLikeTheOldOneExcept(a, i, x){
result = a.slice(0);
result[i] = x
return result
}
so i'll let arrays make
copies of themselves
copies that are
the same as the original
only different
var pride = new Book("Pride and Prejudice", "Austen", 1813);
var war = new Book("War and Peace", "Tolstoy", 1869);
var zombies = new Book("Pride & Prejudice & Zombies", "Grahame-Smith", 2009);
var books = [pride, war];
var other_books = justLikeTheOldOneExcept(books, 0, zombies);
then i can have
my old array
and
my new array
C ZOMBIES ARE BACK
now i don't have to
expend the effort
to trust you
/* I trust me more than you. */
or me
/* I don't trust me. */
but sometimes you
change my objects too
public void aNefariousBookMethod(Book b) {
b.setTitle("Dirk Gently's Holistic Detective Agency");
}
sometimes i forget
and change them myself
// Going about my sleepy business..
Book war = new Book("War and Peace", "Tolstoy", 1869);
aNefariousBookMethod(war);
// Wait what?
System.out.println(war.title);
it’s been a long night
so let’s have the same rules for objects
and arrays
def justLikeTheOldOneExcept(v, i, x):
result = copy(v)
if isinstance(result, list):
result[i] = x
else:
setattr(result, i, x)
return result
no changing
just modified copies
Book book1 = new Book("War and Peace", "Tolstoy", 1869);
Book book2 = book1.justLikeTheOldOneExcept(
"title",
"Dirk Gently's Holistic Detective Agency");
after all
it's just a dream
// Rules are like spouses. There is an optimal number to have.
now there are fewer
rules to remember
sometimes i make an object
with private fields
class Book {
private String title;
private String author;
private int year_published;
// ...
}
then i discover
that i need
to get at
those private fields
class Book {
private String title;
private String author;
private int year_published;
public String getTitle(){
return title;
}
public String getAuthor(){
return author;
}
public int getYearPublished(){
return year_published;
}
}
so i make them public
C TOTAL UP THE EFFORT
EFFORT = PRIVEFFT + PUBLEFFT
i had to make the
private fields private
and then i had to make
the private fields public
that’s a lot of work
and then it’s more work
class Book {
public String title;
public String author;
public int year_published;
}
it’s just easier to
make all the fields public
after all
why am i hiding from the data?
don't hide from the data
it's just data
class ThoseObjects {
public String title;
public String author;
public String cityPublshed;
public String countryPublished;
public int yearPublishd;
public int editoon;
public int copiesSold;
}
sometimes
and there are
lots of fields
and i get tired of all the typing
and my fingers make mistakes
git ci -m 'Fix misspelling of Book fields.' Book.java
so i’ll just use a
map or a hash or a dictionary
or whatever we call it in this language
and make an open
name/value thing
var pride = {"title": "Pride and Prejudice", "author": "Austen", "published": 1813};
now i can make
new objects full of data
as fast as i can type
which isn’t very fast
since
my eyes are closed
var zombies = {"title": "Pride and Prejudice and Zombies", "author": "Grahame-Smith", "published": 2009};
var war = {"title": "War and Peace", "author": "Tolstoy", "published": 1869};
if all my data
is in
hashes or
dictionaries
or maps
whatever we call them
in this language
then i don’t have a place for my code
interface Function {
public Object invoke(Object arg);
}
class MakeDescription implements Function {
public Object invoke(Object arg) {
Book book = (Book)arg;
return book.get("title") +
" by " +
book.get("author") +
" published in " +
book.get("yearPublished");
}
}
so i’ll just make little
one method
no data
objects
and put my code there
i’ll call these things
functions
that’s a word i learned in
math class
before i feel asleep
var make_description = function (b){
return b.title + " by " + b.author
" published in " + b.published
};
but before the night was over
the dream continued
– Russ
A version of this article originally appeared on Cognitect blog.
