Pony Introduction
by "Blag" - Senior Developer Evangelist
What is Pony?
Pony is an object-oriented, actor-model, capabilities-secure, high performance programming language.
Pony is free and Open Source.
It's type safe...and memory safe...and exception safe...
Pony is an ahead-of-time (AOT) compiled language. There is no interpreter or virtual machine.
How to install Pony?
It can be installed on Windows (Not there yet), Linux and MacOS...but I would recommend Linux.
wget -O - http://releases.ponylang.org/buildbot@lists.ponylang.org.gpg.key | sudo apt-key add -
sudo add-apt-repository "deb http://releases.ponylang.org/apt ponyc main"
sudo apt-get update
sudo apt-get install ponyc
Who uses Pony?
- Too young and still in development...
Starting out...
Pony code needs to be compile before using it...
You need to create a folder where your source code will reside...the name of the folder will be the name of your application.
Inside the folder you main file will be named "main.pony"...
To compile...we need go inside the folder
ponyc "main.pony"
Basic Concepts
Just line in C++ one line comments are // and multiple lines comments are /* and */.
Precedence must be enforced by parenthesis...otherwise you will get an error...
actor Main
new create(env: Env) =>
var number:I8 = (2 * 3) + 5
env.out.print("" + number.string())
Variables
We can create variables using either var or let...
"var" works like any programming language...variables can be reassigned...
"let" works like functional programming...variables cannot be reassigned...
Global variables doesn't even exist...
Arrays are easy...
actor Main
new create(env: Env) =>
var array: Array[String] = ["A","B","C"]
var elem: String = try array(0) else "" end
env.out.print(elem)
for elem in array.values() do
env.out.print(elem)
end
We can create an array of arrays...
actor Main
new create(env: Env) =>
var array: Array[Array[String]] =
[["A","B","C"],["1","2","3"]]
for i in ["0","1"].values() do
for j in ["0","1","2"].values() do
var elem: String =
try array(i.u64())(j.u64())
else "" end
env.out.print(elem)
end
end
In Pony, everything is an expression...that's why we can do something like this...
actor Main
new create(env: Env) =>
var myNumber:I8 = 10
var myAdd:I8 = 5
myNumber = myNumber + if myAdd == 5
then 15 else 1 end
env.out.print(myNumber.string())
One weird thing aboout Pony...in order to create functions...you must create a class...
class Add
fun get_add(a:I32, b:I32): I32 =>
a + b
actor Main
new create(env: Env) =>
let num = Add.get_add(5,8)
env.out.print(num.string())
Fibonacci List
Finally...we're going to make our first application...
So grab your favorite text editor and get ready...
Name your file "main.pony" inside a folder called "fibonacci"
class Fibo
fun get_fibo(num:I32,a:I32,b:I32):String =>
var result:String = ""
if (a > 0) and (num > 1) then
result = result + (a+b).string() + " " +
get_fibo(num-1,a+b,a)
elseif (a == 0) then
result = a.string() + " " + b.string() +
" " + (a+b).string() + " " +
get_fibo(num-1,a+b,b)
end
result
actor Main
new create(env: Env) =>
var sNum:String = try env.args(1) else "" end
var num:I32 = try sNum.i32() else 0 end
var line:String = Fibo.get_fibo(num,0,1)
env.out.print(line)
Open the Terminal and go to your source code folder...
ponyc
When we run it we're going to see...
Making an LED Number App
This is one of my favorite codes because it helps you learn a new language...
Name your file "main.pony" inside a folder called "lednumbers"
actor Main
new create(env: Env) =>
let leds: Array[Array[String]] =
[[" _ ","| | ","|_| "],
[" ","| ","| "],
[" _ "," _| ","|_ "],
["_ ","_| ","_| "],
[" ","|_| "," | "],
[" _ ","|_ "," _| "],
[" _ ","|_ ","|_| "],
["_ "," | "," | "],
[" _ ","|_| ","|_| "],
[" _ ","|_| "," _| "]]
var num: String = try env.args(1) else "" end
var i: I64 = 0
var j: I64 = 0
var line: String = ""
var sizec: I64 = try num.size().string().i64()
else 0 end
while i < 3 do
while j < sizec do
try line =
line.insert(line.size().string().i64(),
leds(num.substring(j,j).u64())
(i.string().u64())) else "" end
j = j + 1
end
i = i + 1
j = 0
env.out.print(line)
line = ""
end
env.out.print("")
When we run it we're going to see...
Random Names
This App will generate 100,000 random names using two 16 elements arrays
We will measure the runtime
Name your file "main.pony" inside a folder called "random_names"
use "collections"
use "random"
actor Main
new create(env: Env) =>
let names:Array[String] = ["Anne","Gigi","Blag",
"Juergen","Marek",
"Ingo","Lars","Julia",
"Danielle","Rocky",
"Julien","Uwe","Myles",
"Mike","Steven","Fanny"]
let last_names: Array[String] = ["Hardy","Read",
"Tejada",
"Schmerder",
"Kowalkiewicz",
"Sauerzapf",
"Karg","Satsuta",
"Keene",
"Ongkowidjojo",
"Vayssiere",
"Kylau","Fenlon",
"Flynn","Taylor",
"Tan"]
var elem1: String = ""
var elem2: String = ""
var full_names: Array[String] = [""]
let dice = Dice(MT)
for i in Range(0, 100000) do
elem1 = try names(dice(1,16) - 1)
else "" end
elem2 = try last_names(dice(1,16) - 1)
else "" end
try full_names.insert(0,elem1 + " " + elem2)
else "" end
end
When we run it we're going to see...
How this behaves in Python?
What about Julia?
Decimal to Romans
This App will create a Roman Numeral based on a decimal number
This will include some nice commands...
Name your file "main.pony" inside a folder called "decimal_to_romans"
class Romans
fun get_romans(num:I32,ctr:U64,
result:String):String =>
var response:String = ""
let roman_nums: Array[Array[String]] =
[["1000","M"],["900","CM"],
["500","D"],["400","CD"],
["100","C"],["90","XC"],
["50","L"],["40","XL"],
["10","X"],["9","IX"],
["5","V"],["4","IV"],
["1","I"]]
var line:String = try roman_nums(ctr)(0)
else "" end
var iline = try line.i32() else 0 end
if(num >= iline) then
var value:String = try roman_nums(ctr)(1)
else "" end
response = value +
get_romans((num - iline), ctr,
result)
elseif (num < iline) and (num > 0) then
response = get_romans(num, (ctr + 1),
result)
end
response
actor Main
new create(env: Env) =>
var sNum:String = try env.args(1) else "" end
var num:I32 = try sNum.i32() else 0 end
var result:String = ""
result = Romans.get_romans(num,0,"")
env.out.print(result)
When we run it we're going to see...
Is that all?
Sadly...it is...
Pony is still more than fresh...heck! they don't even have a proper logo...but some nice people are working
pretty heavily trying to make it work in the best and fast possible way...so stay tuned and look for more Pony in the near future...
I'm sure that Pony will cause a pretty big impact when it got finally "officially released"...
Contact Information
Blag --> blag@blagarts.com
@Blag on Twitter
