KITE: language in C for Termux and Android

KITE: A Handcrafted Programming Language in C for Termux

A developer has implemented the KITE programming language in pure C, compiling it to run in Termux on Android. The interpreter uses a classic architecture: lexer, parser, and tree-walking interpreter. The total codebase is about 3200 lines, with a focus on performance through reference counting instead of garbage collection.

The syntax is designed for readability: no semicolons, blocks using colons and end. Variables are declared with set, conditional constructs are when/orwhen/else, and return is give.

Example basic code:

set name = "world"
say("Hello, ${name}!")

def factorial(n):
    when n <= 1: give 1 end
    give n * factorial(n - 1)
end

loop for i in range(10):
    say("${i}! = ${factorial(i)}")
end

Interpreter Architecture

Lexer

The lexer (lexer.c, ~200 lines) tokenizes source code. It supports string interpolation ${}: "Hello, ${name}!" becomes TK_FMTSTR with subexpressions. Tokens: TK_SET, TK_IDENT, TK_NUM, TK_PLUS, etc.

Parser

A recursive descent parser (parser.c, ~700 lines) builds the AST. Nodes are enum NKind:

typedef enum {
    ND_NUM, ND_STR, ND_FMTSTR, ND_BOOL, ND_NIL,
    ND_SET, ND_ASSIGN, ND_BINOP, ND_UNOP,
    ND_CALL, ND_INDEX, ND_PROP,
    ND_DEF, ND_WHEN, ND_LOOP_WHILE, ND_LOOP_FOR,
    ND_DO, ND_OBJ, ND_GIVE, ND_BREAK, ND_NEXT,
    /* ... */
} NKind;

Expression precedence: assign → or → and → not → cmp → add → mul → pow → unary → postfix → primary.

Interpreter

The tree-walking interpreter (interp.c, ~1600 lines) recursively traverses the AST:

Value *eval(Interp *ip, Node *n, Env *env) {
    switch (n->kind) {
        case ND_NUM:  return val_num(n->num);
        case ND_SET: {
            Value *v = eval(ip, n->set.val, env);
            env_def(env, n->set.name, v);
            return val_nil();
        }
        /* ... */
    }
}

Memory Management and Closures

Reference counting in the Value structure:

struct Value {
    VType type;
    int   refs;
    union { double num; char *str; KiteList *list; /* ... */ };
};

val_ref() / val_unref() manage deallocation. Closures capture Env:

typedef struct KiteFn {
    char  *name;
    char **params;
    int    nparams;
    Node  *body;
    Env   *closure;
    int    refs;
} KiteFn;

Example:

def make_counter(start):
    set count = start
    def inc():
        count += 1
        give count
    end
    give inc
end

set c = make_counter(0)
say(c())   # 1
say(c())   # 2

Object-Oriented Programming

OOP via obj: classes are KiteClass with methods, instances are KiteInstance with fields. Inheritance, super, private fields with _.

obj Animal:
    set name = nil

    def init(self, name):
        self.name = name
    end

    def speak(self):
        say("${self.name} makes a sound")
    end
end

obj Dog extends Animal:
    set _tricks = 0

    def learn(self):
        self._tricks += 1
    end

    def speak(self):
        super.speak(self)
        say("${self.name}: Woof!")
    end
end

set d = Dog.new("Buddy")
d.learn()
d.speak()
say(d is Dog)       # true

Error Handling and Standard Libraries

do/err blocks:

do:
    set data = file_read("config.txt")
err IOError:
    say("File not found, creating...")
    file_create("config.txt")
err:
    say("Unexpected error: ${err_msg}")
end

Error types: ZeroDivisionError, NameError, IndexError, TypeError, IOError, AccessError.

Standard modules:

• math: tan, log2, clamp, lerp
• rand: rand(), rand_choice()
• string: str_pad_left, str_count
• list: list_sum, list_zip
• io: file_read, file_lines
• os: os_env, os_shell

Compilation and Running in Termux

Installation:

• pkg install clang make
• tar -xzf kite-lang.tar.gz
• cd kite-lang
• make CC=clang
• cp kite $PREFIX/bin/kite
• kite --version

REPL support, vim/micro with syntax highlighting.

File statistics:

| File | Lines | Role |

|----------|-------|-----------------------|

| kite.h | ~250 | Types, AST |

| lexer.c | ~200 | Tokenizer |

| parser.c | ~700 | Parser |

| value.c | ~300 | Values, refcount |

| interp.c | ~1600 | Interpreter |

| main.c | ~120 | REPL, entry |

Total: ~3200 lines.

Key Takeaways

• Minimalist syntax with set/when/give for readability and error prevention.
• Reference counting without GC ensures predictable performance.
• Full-featured OOP with inheritance, closures, and encapsulation.
• Compilation on Android/Termux without dependencies.
• Open source (MIT), ready for forks and PRs.

— Editorial Team