Aldor

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For the Middle-earth character, see Aldor (Middle-earth).
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; 27 years ago (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.aldor.org
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[edit]

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
99 Bottles of Beer
#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();

External links[edit]