the-watchmaker/yamas

WIP - Programmable YAML

Fujiyama¹

Yamas

YAMAS stand for Yet Another Markup As Script

Why?

I use lots of YAML in different apps. They all have their own implicit logic behind data structure and documentation. Nowadays, YAML is being used as near-script language anyways. (Also it looks like Python.)

Design

1. Super simple
2. No native loops
3. Limited native functions:
   • ECHO@
   • LINE@
   • HTTP@
   • BASH@
   • PARSE@

Variables and memory management

Use Rust's "ownership" concept.

• A variable ownership can be passed around using @TAKE and @PUT.
• Only @RUN can be the owner (should we change the name @RUN to @THREAD to make it more clear? 🤔)
• Once @RUN is run, values in variables are dropped and cleaned

Syntax

"Hello World"

THREAD@:
  - ECHO@: "Hello World \n"
  - LINE@: "Hello World"

If

RUN@:
  - SET@:
      - NAME@: hello
        VALUE@: "world"
  - SET@
      - NAME@: peace
      - VALUE@: true
  - IF@:
      AND@:
        - EQ@: 
          - ${hello}
          - "world"
        - EQ@:
          - ${peace}
          - true
      THEN@:
        - ECHO@: |
           Hello World! 

Go to

RUN@:
  - SET@:
      - NAME@: hello
        VALUE@: world
  - IF@:
      - EQ@: 
        - ${hello}
        - "world"
      THEN@:
        - GOTO@: 1
        - GOTO@: 2
        - GOTO@: 3
  - LOC_1@:
      - ECHO@: Hello
      - RETURN@
  - LOC_2@:
      - ECHO@: " World"
      - RETURN@
  - LOC_3@:
      - ECHO@: "\n"
      - RETURN@

Function Call

RUN@:
  - FN@: World
    TAKE@:
      - greeting
    RUN@:
      - IF@: ${greeting} == "world"
        THEN@:
          - RETURN: "World"
  - ECHO@:
      FROM@:
        - "Hello"
        - FROM_CALL@: World
          PUT@:
            - greeting: "Hello"

Statements & declarations

• FROM@

RUN@:
  - ECHO@:
      FROM@:
        - "Hello"
        - " World"
        - "\n"

Native methods

• PARSE@

PARSE@:
   KIND@: JSON
   FROM@: |
      { 
        "foo": "bar", 
        "soo": "taa", 
        "bip": {
          "bap": "boop"
        }
      }
   SET_FROM@:
      - bipbap: "bip.bap"
ECHO@: ${bipbap}

Expressions & operators

• EQ@, NE@, GT@, L@, GTE@, LTE@

EQ@:
   - ${foo}
   - "bar"

 foo === "bar"

• ADD@, SUB@, MUL@, DIV@

@SET_NUM:
   - "added"
   - @FROM:
      - @ADD
         - ${added}
         - 1

 added = added + 1;

Some random reading

• How to Build a New Programming Language by Pietro Gradinetti
• Designing a Programing Language By DuckLang.org
• Programming Language Design by Saeed Mohajeryami
• Syntax Design by LMU CS
• Creating A Programming Language From Scratch by Joao Zsigmond
• Rust and RAII Memory Management by Computerphile

Footnotes

1. Photo by Jules Marvin Eguilos on Unsplash ↩