Aldor
| Paradigm | Multi-paradigm: object-oriented, functional, imperative, dependent typed, logic |
|---|---|
| Designed by | Richard Dimick Jenks, Barry Trager, Stephen Watt, James Davenport, Robert Sutor, Scott Morrison |
| Developer | Thomas J. Watson Research Center |
| First appeared | 1990 |
| Stable release |
1.0.3
|
| Preview release |
1.1.0
|
| Platform | Axiom computer algebra system |
| OS | Linux, Solaris, Windows |
| License | Aldor Public 2.0, Apache 2.0 |
| Filename extensions | .al, .as |
| Website |
www |
| Major implementations | |
| Axiom computer algebra system | |
| Influenced by | |
| A#, Pascal, Haskell | |
Aldor is a programming language. It is the successor of A# as the extension language of the Axiom computer algebra system.
Aldor combines imperative, functional, and object-oriented features. It has an elaborate type system,"Aldor Programming Language". Aldor.org. Retrieved 12 February 2017. allowing types to be used as first-class values. Aldor's syntax is heavily influenced by Pascal, but it is optionally indentation-sensitive, using whitespace characters and the off-side rule, like Python. In its current implementation, it is compiled, but an interactive listener is provided.
Aldor is distributed as free and open-source software, under the Apache License 2.0.
Examples
The Hello world program looks like this:
#include "aldor"
#include "aldorio"
stdout << "Hello, world!" << newline;
Example of dependent types (from the User Guide):
#include "aldor"
#include "aldorio"
#pile
sumlist(R: ArithmeticType, l: List R): R ==
s: R := 0;
for x in l repeat s := s + x
s
import from List Integer, Integer, List SingleFloat, SingleFloat
stdout << sumlist(Integer, [2,3,4,5]) << newline
stdout << sumlist(SingleFloat, [2.0, 2.1, 2.2, 2.4]) << newline
#include "aldor"
#include "aldorio"
import from Integer, String;
bob(n: Integer): String == {
b: String := " bottle";
if n ~= 1 then b := b + "s";
b + " of beer";
}
main(): () == {
n: Integer := 99;
otw: String := " on the wall";
-- refrain
while n > 0 repeat {
stdout << n << bob(n) << otw << ", " << n << bob(n) << "." << newline;
stdout << "Take one down and pass it around, ";
n := n - 1;
if n > 0 then stdout << n;
else stdout << "no more";
stdout << bob(n) << otw << "." << newline;
stdout << newline;
}
-- last verse
stdout << "No more" << bob(n) << otw << ", no more" << bob(n) << "." << newline;
stdout << "Go to the store and buy some more, ";
n: Integer := 99;
stdout << n << bob(n) << otw << "." << newline;
}
main();