re:fi.64

The top 5 programming languages you've never heard of (part 2)

The top 5 programming languages you've never heard of (part 2)

Created on 2015-03-08 - Comments

Yesterday, I wrote a post about the top 5 programming languages you've never heard of . Well, since it was kind of short (I didn't have too much time to write), I'm going to put a little more info here.

Nim link

I enjoy coding in Nim because it's fun. Nim's goal is seemingly to blur the line between compiled and scripting languages, and it's doing a GREAT job. The compiler is self-hosting, but it's not quite the prime example of a well-written Nim program (it was ported from Object Pascal). A better example is Nimble: the Nim package manager. Here's a piece of Nimble's source code:

proc update(options: Options) =
  ## Downloads the package list from the specified URL.
  ##
  ## If the download is successful, the global didUpdatePackages is set to
  ## true. Otherwise an exception is raised on error.
  let url =
    if options.action.typ == actionUpdate and options.action.optionalURL != "":
      options.action.optionalURL
    else:
      defaultPackageURL
  echo("Downloading package list from " & url)
  downloadFile(url, options.getNimbleDir() / "packages.json")
  echo("Done.")

A longer piece:

proc parseConfig*(): Config =
  result = initConfig()
  var confFile = getConfigDir() / "nimble" / "nimble.ini"

  var f = newFileStream(confFile, fmRead)
  if f == nil:
    # Try the old deprecated babel.ini
    confFile = getConfigDir() / "babel" / "babel.ini"
    f = newFileStream(confFile, fmRead)
    if f != nil:
      echo("[Warning] Using deprecated config file at ", confFile)

  if f != nil:
    echo("Reading from config file at ", confFile)
    var p: CfgParser
    open(p, f, confFile)
    while true:
      var e = next(p)
      case e.kind
      of cfgEof:
        break
      of cfgSectionStart: discard
      of cfgKeyValuePair, cfgOption:
        case e.key.normalize
        of "nimbledir":
          # Ensure we don't restore the deprecated nimble dir.
          if e.value != getHomeDir() / ".babel":
            result.nimbleDir = e.value
        of "chcp":
          result.chcp = parseBool(e.value)
        else:
          raise newException(NimbleError, "Unable to parse config file:" &
                                  " Unknown key: " & e.key)
      of cfgError:
        raise newException(NimbleError, "Unable to parse config file: " & e.msg)
    close(p)

Felix link

Felix is unique. It's a mix of C++, ML, and lots of unique ideas. Here's a nice sample from a toy JSON parser I was writing (this is only the lexer part):

class JSON {
    typedef LineType = int;

    union Value =
        | Object of strdict[Value]
        | Array  of list[Value]
        | String of string
        | Number of double
        | True
        | False
        | Null
        | Error of string * LineType
    ;

    union Token =
        | TString of string
        | TNumber of double
        | TLBrace // {
        | TRBrace // }
        | TLBrak  // [
        | TRBrak  // ]
        | TColon  // :
        | TTrue   // true
        | TFalse  // false
        | TNull   // null
        | TEOF
        | TError of string * LineType
    ;

    instance Str[Token] {
        fun str(t: Token) => match t with
            | TString ?s => "TString \"" + s + "\""
            | TNumber ?n => "TNumber " + n.str
            | TLBrace    => "TLBrace"
            | TRBrace    => "TRBrace"
            | TLBrak     => "TLBrak"
            | TRBrak     => "TRBrak"
            | TColon     => "TColon"
            | TTrue      => "TTrue"
            | TFalse     => "TFalse"
            | TNull      => "TNull"
            | TEOF       => "TEOF"
            | TError (?s, ?i) => "error at line " + i.str + ": " + s
        endmatch;
    }

    proc lex(s: string, line: &LineType, outs: oschannel[Token]) = {
        line <- 1;

        proc tok(t: Token) => write $ outs, t;

        proc err(s: string) = {
            tok $ TError(s, *line);
            return from lex;
        };

        var i = 0.size;

        while i < s.len do
            while s.[i].isspace do
                if s.[i] == "\n" do *line++; done;
                i++;
                if i >= s.len goto eof;
            done;

            // number
            if s.[i].isnumeric or (i+1 < s.len and s.[i] == "-" and
                                     s.[i+1].isnumeric) do
                d := s.[i to].double;
                i += d.str.len;
                tok $ TNumber d;
            // string
            elif s.[i] == "\"" do
                i++;
                var st = "";
                while i < s.len and s.[i] != "\n" and s.[i] != "\"" do
                    st += s.[i];
                    i++;
                done;
                if s.[i] != "\"" call err "unterminated string literal";
                i++;
                tok $ TString st;
            // literals
            elif s.[i to i+4] == "true" do
                tok $ TTrue;
                i += 4.size;
            elif s.[i to i+5] == "false" do
                tok $ TFalse;
                i += 5.size;
            elif s.[i to i+4] == "null" do
                tok $ TNull;
                i += 4.size;
            // others
            else
                match s.[i].str with
                    | "{" => tok TLBrace;
                    | "}" => tok TRBrace;
                    | "[" => tok TLBrak;
                    | "]" => tok TRBrak;
                    | ":" => tok TColon;
                    | _   => err "unknown token";
                endmatch;

                i++;
            done;
        done;

        eof:>
        tok TEOF;
    }
}

Here's a link to Felix's own JSON parser, which is written more nicely than mine is...

It illustrates some nice features, such as schannels (coroutines on steroids). schannels are like Go's channels, but not concurrent. Felix has another Go-like channel named fchannels, which are concurrent.

Felix also has a nice set of utilities (a web server, a literate programming format, an alpha-quality graphical config tool) and a decently-sized standard library.

Cons? Very little documentation. However, the mailing list is very responsive.

Myrddin link

Myrddin is essentially how C would probably look if it were designed right now. Some features:

  • Type inference

  • Pattern matching

  • Go-style slices

  • C-style memory management

All in a C-style language. I've been toying with writing a kernel in it, and it's been going very well. I have a lot of hope in Myrddin.

A great example is the libbio input/output library. Here's a snippet:

/*
writes to as much from `src` as possible to a file,
returning the number of bytes written.
*/
const write = {f, src
    std.assert(f.mode & Wr != 0, "File is not in write mode")
    /*
    Tack small writes onto the buffer end. Big ones
    flush the buffer and then go right to kernel.
    */
    if src.len < (f.wbuf.len - f.wend)
        std.slcp(f.wbuf[f.wend:f.wend+src.len], src)
        f.wend += src.len
        -> src.len
    else
        flush(f)
        -> writebuf(f.fd, src)
    ;;
}

However, the compiler generates VERY slow x64 assembly code at the moment...and only x64 assembly code. I'm working on a C backend, though, but it'll be a while until it's finished.

K link

K , along with Kona (an open-source K implementation with bad error messages) is special. It's the result of shoving APL into an ASCII-character world.

Here are some of the idioms at the Kona wiki :

shuffle:{x@<>(#x)#1 0} / Perfect shuffle
mean:{(+/x)%#x} / Arithmetic mean
fac:*/1+!: / Factorial
fib:{x{x,+/-2#x}/!2} / Fibonacci
life:{|/(1;x)&3 4=\:+/,/2{-1 0 1!'\:x}/x} / Conway's Game of Life
sort:{x@<x} / Sort list
powerset:{x[&:'!2+&#x]} / Powerset

As you can see, K is very concise. A little too concise. However, as an array-processing language, it's great for iterating over large sequences of data, as kdb+ has shown. It's also very fast and lean (I'm speaking for kdb+, though, not Kona).

If you can't already tell, the main con is that no one that doesn't know K will be able to read your programs without getting a seizure.

Objeck link

As I said before, Objeck is kind of like I envisioned Java to be, other than the (painful) lack of generics.

It's pretty expressive and nice to work with:

class Factorial {
    function : native : Factorial(n : Int) ~ Int {
        if (n <= 1) {
            return n;
        } else {
            return n * Factorial(n-1);
        };
    }

    function : Main(args : String[]) ~ Nil {
        "Number: "->Print();
        number := IO.Console->ReadString()->ToInt();
        if (number < 0) {
            "Number must be greater than 0"->PrintLine();
            Runtime->Exit(1);
        };
        Factorial(number)->PrintLine();
    }
}

It's very Java-esque but nicer to use. The cons would be the fact that there is no true native compiler . Sure, there's a "compiler", but it's like the Java compiler: it compiles to a bytecode that's executed by a VM. It Objeck's case, the VM is obe . You also have to manually specify that a function is native for it to be compiled to machine code. There also seem to be no unsigned types or operator overloading. Again.

Others link

Two honorable, discontinued mentions are ani and Alore .

Ani is a programming language that would have sported implicit parallelism and very nice speed. Note that I said would have . A working compiler was never fully completed and the maintainer disappeared, so this language may never quite see the light of day. The project mailing list is still there, though, so there are hopes that someday, someone may indeed restart the project.

Alore was a language based on the ability to freely mix static and dynamic typing. Although it was a great idea, the language itself seemingly never caught on, and it was abandoned in favor of mypy , a project with the same basic idea but implemented as a static type checker for Python.

Summary link

That's all! As I said before, I hope one of the languages mentioned caught your eye.