Aldor
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Paradigm | multi-paradigm: object-oriented, functional, imperative, dependent typed, logic programming |
---|---|
Designed by | Richard Dimick Jenks, Barry Trager, Stephen Watt, James Davenport, Robert Sutor, Scott Morrison |
Developer | IBM Thomas J. Watson Research Center |
Platform | Axiom computer algebra system |
License | Apache License |
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.
The Aldor language combines imperative, functional, and object-oriented features. It has an elaborate type system[citation needed], allowing types to be used as first-class values. Aldor's syntax is heavily influenced by Pascal, but it is optionally indentation-sensitive, like Python. In its current implementation, it is compiled, but an interactive listener is provided.
Aldor is Free software, available under the Apache License.
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();