asciidots 1.0.6

Interpreter for the AsciiDots esolang.

AsciiDots - Esoteric Language
=============================

Language By Aaron Janse
'''''''''''''''''''''''

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::

_ _ _____ _
/\ (_|_) __ \ | |
/ \ ___ ___ _ _| | | | ___ | |_ ___
/ /\ \ / __|/ __| | | | | |/ _ \| __/ __|
/ ____ \\__ \ (__| | | |__| | (_) | |_\__ \
/_/ \_\___/\___|_|_|_____/ \___/ \__|___/

AsciiDots is an esoteric programming language based on ascii art. In
this language, *dots*, represented by periods (``.``), travel down ascii
art paths and undergo operations.

`Read comments on Hacker
News <https://news.ycombinator.com/item?id=14947449>`__

|AsciiDots being run in debug mode|

**`Try it online (debugger) <https://aaronduino.github.io/asciidots/demo>`__**
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

**`Try it online (tio.run) <https://tio.run/#asciidots>`__**
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Table of Contents
'''''''''''''''''

`Samples <#samples>`__\ `Using the
Interpreter <#using-the-interpreter>`__\ `Program
Syntax <#program-syntax>`__\ `More Examples <#examples>`__

Samples
-------

Hello world:

::

.-$"Hello, World!"

`Quine <https://en.wikipedia.org/wiki/Quine_(computing)>`__:

::

($'.-#40-$_a#-#36-$_a#-#39-$_a#)

Counter:

::

/1#-.
|
/-+-$#\
| | |
[+]<1#-*
| |
\--<--/
|
0
#
|
.

Semi-compact factorial calculator:

::

/---------*--~-$#-&
| /--;---\| [!]-\
| *------++--*#1/
| | /1#\ ||
[*]*{-}-*~<+*?#-.
*-------+-</
\-#0----/

Code-golfed counter (15 bytes) by @ddorn:

::

/.*$#-\
\{+}1#/

Installing
----------

Clone the repo...

::

git clone https://github.com/aaronduino/asciidots

...install click...

::

pip3 install click

...and run as shown in the next section:

Using the Interpreter
---------------------

The interpreter for this language is the ``__main__.py`` file. It
requires Python 3, and can be run from the terminal using the
``python3`` command. The first argument is the ``dots`` file that you
wish the interpreter to run.

Here's an example of running the counter sample program (the working
directory is the dots repo folder):

.. code:: bash

$ python3 __main__.py ./samples/counter.dots

Here is the list of available flags:

::

-t [ticks] Run the program for a specified number of ticks (Default to 0: no limit)

-o [output-limit] Run the program for a specified number of outputs (Default to 0: no limit)

-s Run without printing ANYTHING to the console. Useful for benchmarking

-d Run the program in debug mode. It shows the program and highlights the dots with red. Press enter to step the program once.

Some extra flags when debugging:
-a [delay] Step the program automatically, using the specified delay in seconds. Decimal numbers are permitted, and so is 0.

-w Run the program without using ncurses. This can fix problems related to Windows.

-l [line-count] When not in compatibility mode, reserve the specified number of the lines for displaying the program

This is how one might debug a program for 300 ticks while running it
automatically with a delay of 0.05 seconds:

.. code:: bash

$ python3 __main__.py ./samples/counter.dots -t 300 -d -a 0.05

Program Syntax
--------------

Basics
~~~~~~

Starting a program
~~~~~~~~~~~~~~~~~~

``.`` (a period), or ``•`` (a bullet symbol), signifies the starting
location of a *dot*, the name for this language's information-carrying
unit. Each dot is initialized with both an `id and
value <#ids-and-values>`__ of ``0``.

Ending a program
~~~~~~~~~~~~~~~~

Interpretation of a dots program ends when a dot passes over an ``&``.
It also ends when all dots die (i.e. they all pass over the end of a
path into nothingness)

Comments
~~~~~~~~

Everything after `````` (two back ticks) is a comment and is ignored by
the interpreter

Paths
~~~~~

``|`` (vertical pipe symbol) is a vertical path that dots travel along
``-`` is a horizontal path that dots travel along

*Note*: For the sake of clarity, only one path should be adjacent to a
starting dot location, so that there is no question where it should go.
The interpreter doesn't make a fuss if you disregard this

Here's an example program that just starts then ends (note that programs
aren't always written and run top-to-bottom):

::

. `` This is where the program starts
| `` The dot travels downwards
| `` Keep on going!
& `` The program ends

Think as these two paths as mirrors: ``/``\ ``\``

So... here's a more complex program demonstrating the use of paths (it
still just starts then ends):

::



/-& `` This is where the program ends!
|
\-\ /-\
| | |
/-/ | \-\
\---/ |
|
\-. `` Here's where the program starts

Special Paths
^^^^^^^^^^^^^

``+`` is the crossing of paths (they do not interact)

``>`` acts like a regular, 2-way, horizontal, path, except dots can be
inserted into the path from the bottom or the top. Those dots will go to
the right ``<`` does likewise except new dots go to the left ``^``
(caret) does this but upwards ``v`` (the lowercase letter 'v') does
likewise but downwards

Here's a way to bounce a dot backwards along its original path using
these symbols:

::

/->-- `` Input/output comes through here
| |
\-/

But there is an easier way to do that:

``(`` reflects a dot backwards along its original path. It accepts dot
coming from the left, and lets them pass through to the right ``)`` does
likewise but for the opposite direction

``*`` duplicates a dot and distributes copies including the original dot
to all attached paths except the origin of dot

Here's a fun example of using these special paths. Don't worry—we'll
soon be able to do more than just start then end a program.

::

/-\ /-& `` End
| | |
\-+-v
| | /-\
(-<-/ | | |
| \-<-/
\-\
|
. `` Start

IDs and Values
~~~~~~~~~~~~~~

``#`` sets the value of the dot to the value after it ``@`` does the
same except it sets the *id* of the dot

| The id has nothing to do with the value.
| Yes this is very confusing (see `open issue about name change
suggestions <https://github.com/aaronduino/asciidots/issues/18>`__).

| The rationale behind having an ``id`` is so that dots can be
differentiated without needing to reserve specific values as having
special meaning (ex. saying ``-1`` that means ``null``).
| The ``id`` can be set to a special value to differentiate dots.
| The common use case of this is having the last dot in a stream of dots
have a different id than the rest, that way the program knows when the
stream has ended.

This sets the value of the dot to ``7``:

::

.-#7-& `` We'll actually do things soon

This sets the id to ``8``:

::

.-@8-&

By the end of this program, the dot's value is ``3``:

::

.-#18-#0-#6-#148-#13-#3-&

By the end of this program, the dot's value is ``13`` and its id is
``99``:

::

.-#7-#0-@278-#17-#8-@4-#0-@99-#1-#13-&

Interactive Console
~~~~~~~~~~~~~~~~~~~

``$`` is the output console. If there are single/double quotation marks
(``'`` or ``"``), it outputs the text after it until there are closing
quotation marks. ``#`` and ``@`` are substituted with the dot's value
and id, respectively     When ``_`` follows a ``$``, the program does
not end printing with a
`newline <https://en.wikipedia.org/wiki/Newline>`__.     When not in
quotes, if a ``a`` comes before a ``#`` or ``@`` symbol, the value is
converted to ascii before it is printed

*Note*: Double quotes (``"``) are buffered. Single quotes (``'``) are
not buffered. The advantage of buffering is that it prevents race
conditions from interleaving text.

Here's how to set and then print a dot's value:

::

. `` This dot is the data carrier
| `` Travel along these vertical paths
# `` Set the value...
3 `` ... to 3
| `` Continue down the path
$ `` Output to the console...
# `` ... the dot's value

Here's our hello world again:

::

.-$"Hello, World!"

Here's how to print that character 'h' without a newline:

::

.-$_"h"

And this prints '%' using the ascii code 37:

::

.-#37-$a#

``?`` is input from the console. It prompts the user for a value, and
pauses until a value is entered in. It only runs after a ``#`` or ``@``
symbol

::

. `` Start
|
# `` Get ready to set the value
? `` Prompt the user
|
$
# `` Print that value to the console
`` Since the only dot goes off the end of the path, it dies. Since no dots are left, the program ends

Control Flow
~~~~~~~~~~~~

``~`` (tilde) redirects dots going through it horizontally to the upward
path if a dot waiting at the bottom has a value *not* equal to ``0``.
Otherwise, the dot continues horizontally. If an exclamation point
(``!``) is under it, then it redirects the dot upwards only if the value
of the dot waiting *is* equal to zero.     ``!`` acts like a pipe.
Special function described above

This example prompts for a value then prints to the console whether the
user provided value is equal to zero:

::

/-$"The value is not equal to zero"
|
.-~-$"The value is equal to zero"
|
?
#
|
.

Operations
~~~~~~~~~~

``[*]`` multiplies the value that passes through vertically by the value
that runs into it horizontally. When a dot arrive here, it waits for
another dot to arrive from a perpendicular direction. When that dot
arrives, the dot that arrived from the top or bottom has its value
updated and it continues through the opposite side. The dot that passed
through horizontally is deleted. ``{*}`` does likewise except it
multiplies the value that enters horizontally by the value that enters
vertically. The resulting dot exits horizontally

Other operations work similarly but with a different symbol in the
middle. This is the key to these symbols: ``*``: multiplication ``/``:
division ``+``: addition ``-``: subtraction ``%``: modulus ``^``:
exponent ``&``: boolean AND ``o``: boolean OR ``x``: boolean XOR ``>``:
greater than ``G``: greater than or equal to ``<``: less than ``L``:
less than or equal to ``=``: equal to ``!``: not equal to

Boolean operations return a dot with a value of ``1`` if the expression
evaluates to true and ``0`` if false.

These characters are only considered operators when located within
brackets. When outside of brackets, symbols like ``*`` perform their
regular functions as described earlier.

Example:

::

`` Simple subtraction:
`` (3 - 2 = 1)

#
$
|
[-]-2#-.
|
3
#
|
.

Add two user inputted values together then output the sum:

::

.-#?-{+}-$#
|
.-#?--/

Warps
~~~~~

A warp is a character that teleports, or 'warps', a dot to the other
occurrence of the same letter in the program.

Define warps at the beginning of the file by listing them after a
``%$``. The ``%$`` must be at the beginning of the line.

Example:

::

%$A

.-#9-A `` Create a dot, set its value to 9, then warp it

A-$# `` Print the dot's value (9)

Here's a fun example of using warps (although it is not very useful in
this case)

::


%$A

# /-)
$ |
\>-A
\-3#-.

A-\
\-/

Libraries
---------

Dots supports libraries! A library is a program that defines a character
(usually a letter).

Using Libraries
^^^^^^^^^^^^^^^

A library can be imported by starting a line with ``%!``, followed with
the file name, followed with a single space and then the character that
the library defines.

By default, all copies of the character to lead to the same
(`singleton <https://en.wikipedia.org/wiki/Singleton_pattern>`__)
library code. This can cause some unexpected behavior if the library
returns an old dot, since that old dot will come out of the char that
*it* came from.

Here's an example of importing the standard ``for_in_range`` library
(located in the ``libs`` folder) as the character ``f``:

::

%!for_in_range.dots f

The way to use a library varies. Inputs and outputs of the library are
through the alias character.

For the ``for_in_range`` library, the inputs are defined as follows: -
The dot coming from the **left** side sets the starting value of the
counter - The dot coming from the **right** sets the end value of the
Counter

And the outputs are as follows: - A dot for each number within the range
defined by the inputs is output from the **top** - When the loop is
complete (the end value has been reached), a dot is output from the
**bottom**

Here is an example of outputting all the numbers between ``1`` and
``100`` to the console, then stopping the program:

::

%!for_in_range.dots f

#
$
|
.-*-#1---f-\
\-#100-+-/
|
&

Creating Libraries
^^^^^^^^^^^^^^^^^^

Each library defined a character that will act as a warp to & from the
library.

That can be done like so:

::

%$X `` X could be replaced with a different character, if so desired

It is recommended that you create warps for different sides of the char.
Just look at the example code for the ``val_to_addr.dots`` library:

::

%^X
%$AB

B-X-A


A-*----@{+}-#0-B
| |
\------/

Interpretation
--------------

Each tick, the dots will travel along the lines until they hit a charter
that acts as a function of multiple dots (i.e. an operation character or
a ``~`` character). The dot will stop if it goes on a path that it has
already traversed in the same tick

Due to the fact that dots may be moving backwards down a line, if a
number or system value (e.g. ``?``) is seen without a preceding ``@`` or
``#``, it will be ignored, along with any ``@`` or ``#`` immediately
thereafter

Examples
--------

Hello, World!

::

.-$"Hello, World!"

Counter:

::

/1#-.
|
/-+-$#\
| | |
[+]<1#-*
| |
\--<--/
|
0
#
|
.

Find prime numbers:

::

%$T

.
|
#
3
|
@
1
|
/--*--*-<--\
| | | /+----\
| # | v+-0@-~-\
| 2 | /->~*{%}/ |
| | | 1 |\-+---/
| | | @ ^\ |
\-{+}-+-* 01 |
| | ## |
| v--*+-/
| | ||
/-* | *+--\
| T | || |
# $ # /~/ |
0 # 1 */ |
| | | | |
\->-+-~----<-#$-2#-.
\-/


/--------\
T |
*--------~
| |
\-*----@[=]
| |
\--#1--/

This work is licensed under a Creative Commons Attribution-ShareAlike
4.0 International License.

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