analang/ana

Welcome to Ana

Ana is a Python, PHP, and C inspired dynamically typed scripting language that implements object-oriented programing along with imperativeness. Learn more.

Bytecode example.

This screenshot was produced by running:

ana --opcodes -c 'print(1);'

Bytecode example with jump targets

ana --opcodes tests/grammar/if-statements/if-statement.ana --function test_if_statement```

Ana Virtual Machine Disassembler
  Frame: test_if_statement
  Constant Table:
   Index          Value        Type
   0              <function 'r function
   1              readline     string
   2              <function 'p function
   3              print        string
   4              <function 'i function
   5              int          string
   6              <function 't function
   7              typeof       string
   8              1            long
   9              1            long
   10             <function 't function
   11             test_if_stat string
   12             Unexpected r string
   13             ,expected    string
   14             0            long
   15             <function 'e function
   16             expect       string
   17             1            long
   18             1            long
   19             0            long
   20             1            long
   21             0            long
  Jump Targets:
   0              5            long
   1              5            long
  VM Symbols:
   0              push
   1              length
   2              getType
   3              first
   4              length
   5              getBytes
   6              getType
   7              getType
   8              value
   9              value
   10             value
   11             expected
   12             test_if_statement
   13             expect
   14             test_if_statement
   15             expect

0    : LOAD_NAME                8
1    : JMPZ                     0
2    : LOAD_CONST               8
3    : IRETURN                  0

Building

• git clone https://github.com/analang/ana
• cd ana
• make
• ana --version

Features

• Virtual machine
• source to bytecode compiler, intepreted by the VM
• classes with single layered inheritance
• dynamically sized arrays
• built in hash map support
• variadic functions
• simple module system
• built in types
• exceptions
• C based runtime extension system
• garbage collection
• first class functions

cd tests/grammar/import

ana mod.ana

The source code of mod.ana is below:

import logger;
import system.collections.generic.list;

logger.log("Hello World", "Second argument");

list = list.List();
list.add("Hello World");
list.add(logger);

print(list._items);

logger.log("{}", "Welcome to Ana Lang v.0.0.1");

Here's an advanced example which implements a JSON parser. The JSON is provided via stdin and the ana program reads from stdin and converts the JSON string into an abstract syntax tree. The full source code is jsonparser.ana. Note that this JSON parser is incomplete. It currently supports objects, integers, and strings. The strings are primitive, and advanced character handling is not supported yet.

class AstNode {
  function AstNode(kind) {
    self.kind = kind;
    self.children = [];
  }
}

class Buffer
{
  function Buffer(value)
  {
    self.stream   = value;
    self.position = 0;
  }

  function advance()
  {
    if(self.position == self.stream.length())
    {
      throw "Can't advance buffer. Unexpected EOF";
    }

    return stream[self.position++];
  }

  function top()
  {
    return stream[self.position];
  }
}

function parse_int(buffer)
{
  val = 0;

  while(buffer.top() >= '0' && buffer.top() <= '9')
  {
    val = val * 10 + (int(buffer.top()) - int('0'));

    buffer.advance();
  }

  return val;
}

function parse_str(buffer)
{
  val = '';

  while(buffer.top() != '"')
  {
    val += buffer.top();

    buffer.advance();
  }

  buffer.advance();

  return val;
}

function is_int(val)
{
  return val >= '0' && val <= '9';
}

function is_string(val)
{
  return val == '"';
}

function skip_white(buffer)
{
  while(buffer.top() == ' ' || buffer.top() == '\t')
  {
    buffer.advance();
  }
}

function parse_key(buffer)
{
  skip_white(buffer);

  if(buffer.top() != '"')
  {
    throw 'Expected \'"\', not \'' + buffer.top() + '\' to start a key value pair at position ' + buffer.position;
  }

  key = '';
  buffer.advance();

  while(buffer.top() != '"')
  {
    key = key + buffer.top();

    buffer.advance();
  }

  if(buffer.top() != '"')
  {
    throw "Unexpected end of string literal, missing \"";
  }

  buffer.advance();

  return key;
}

class KeyValuePair
{
  function KeyValuePair(key, value)
  {
    self.key = key;
    self.value = value;
  }
}

function parse_object(buffer)
{ 
  node = AstNode("object");

  if(buffer.top() != '{')
  {
    throw "Expected '{' at position " + buffer.position;
  }

  buffer.advance();

  while(buffer.top() != '}')
  { 
    key = parse_key(buffer);

    skip_white(buffer);

    if(buffer.top() != ':')
    {
      throw "Expected ':' after key";
    }

    buffer.advance();

    skip_white(buffer);

    value = parse(buffer);

    node.children.push(KeyValuePair(key, value));

    buffer.advance();
  }

  return node;
}

function parse(buffer)
{
  if(buffer.top() == '{')
  {
    return parse_object(buffer);
  }
  else if(is_int(buffer.top()))
  {
    return parse_int(buffer);
  }
  else if(is_string(buffer.top()))
  {
    buffer.advance();
    return parse_str(buffer);
  }
  else
  {
    throw "Invalid start of JSON object at position " + buffer.position + ", got '" + buffer.top() + "'";
  }
}

function main()
{
  buffer = '';

  while(line = readline())
  {
    buffer = buffer + line;
  }

  buffer = Buffer(buffer);

  result = parse(buffer);

  foreach(kvpair in result.children)
  {
    print(kvpair.key + ":" + kvpair.value);
  }
}

main();