喵谕 Meaoiu

Meaoiu (喵谕) is a cat-themed esoteric programming language. Designed with Chinese keywords, its syntax heavily(maybe) revolves around feline behaviors.

Despite its esoteric and highly stylized nature, Meaoiu provides a suite of modern language features, including a built-in formatting tool, static diagnostics, and a Language Server Protocol (LSP) implementation.

Language Concepts

The Tail (~)

Every valid statement must be terminated with a ~ (This is like ; in most programming languages).

蹭甲~       (Valid, in pseudo code it is "var a;")
蹭乙        (Syntax Error: Missing tail)

Data Types

Meaoiu supports several basic data types, referred to as "Toys" (玩具):

• Number (摸数): IEEE 754 double-precision floating-point numbers. (Note that there's no negative number literal but you can use 0-x to get -x)
• String (闲话): Character strings wrapped in single or double quotes.
• Boolean (好坏): 好喵 (Good Meow / True) and 坏喵 (Bad Meow / False).
• Null (空碗): 空碗 (Empty Bowl), representing nothing.
• Collection (纸箱): Arrays/Dictionaries, represented as Cardboard Boxes [= =].
• Function (计谋): Functions or Schemes. This is not a "Toy".

Variables and Memory Semantics

Variables are declared using the keyword 蹭 (Rub). Meaoiu explicitly differentiates between reference, copy, and move assignments using different keywords:

Keyword	Action	Description
就是 (Is)	Reference	Both variables point to the same memory space.
就像 (Is like)	Copy	Creates a shallow copy of the data for the new variable.
才是 (Is only/truly)	Move	Moves the data to the new variable, disable the original one.

Syntax and Commands

Arithmetic and Chained Operations

Meaoiu supports basic arithmetic (+, -, *, /). It also features a unique "Sequence Operator" (分节运算) using commas to chain arithmetic evaluations from left to right without needing parentheses:

10+2*3 -, 7 *, 2~ 
(Evaluates to ((10 + 2 * 3) - 7) * 2)

Logic Gates

Logical operations use a self-closing pair syntax. Opening and closing keywords must strictly match:

Open	Close	Equivalent to
和 (And)	都好 (All good)	AND
和 (And)	都坏 (All bad)	NOR
或 (Or)	不坏 (Not bad)	OR
或 (Or)	不好 (Not good)	NAND

Example: a 和 b 都好~ means a && b.

Control Flow

Code blocks ("Thoughts") are wrapped in [# #]. The last expression in the block is its return value.

• If/Else: Evaluated using 好不好? (Good or not?) and 不然 (Otherwise). Note that the condition comes after the block.

[# 扒[='Too big'=]喵~ #] 好不好? x > 5
不然 [# 扒[='Too small'=]喵~ #]~ (printLn('Too big') if x > 5 else printLn('Too small'))

• Loops: Initiated with 玩耍 (Play). You can break out using 累了 (Tired) or continue/return early using 偷袭 (Ambush).

Functions

Functions are declared using 想要 (Want), followed by arguments in a box [= =], the function name, and the body in [# #]. To return a value, use 叼回来 (Bring back). (want some items to do something)

The only way to use a declared function is to use 扒 (Paw at) followed by arguments in [= =] and the function name to call it. You can't assign it to another variable or use it as an argument.

(Declaration)
想要 [=n=] 双倍 [#
    叼回来 n * 2~
#]~

(Call)
扒[=5=]双倍~

Built-in Functions

Meaoiu comes with several built-in functions that can be called directly:

• 扒[= 'Text' =]喵~: Print to stdout.
• 扒[= 'Prompt' =]祈求~: Read input from stdin.
• 扒[= 秒数 =]打盹~: Sleep for X seconds. If X is 0 then halt until keystroke.
• 扒[= A, B =]添乱~: Generate a random integer between A and B.
• 扒[= '开心' =]猫咪艺术~: Print an ASCII cat face.

Examples

Hello, World!

扒[='Hello, World!'=]喵~

Sgn Machine

蹭 齉~
(* Don't ask me why I used such a complicated character; the answer is just to avoid keywords.* )
(* Also, please ignore the content inside the parentheses and asterisk combinations; *)
(* that's just a comment and shouldn't appear in the program. *)
齉 就是 扒[= 'Please enter a number: ' =]祈求~
[# 扒[='1'=]喵~ #] 好不好? x > 0
不然 [#
    [# 扒[='-1'=]喵~ #] 好不好? x < 0
    不然 [#
        玩耍 [# 扒[='0'=]喵~ #]~
    #]~
#]~

Fibonacci (Recursion)

想要 [=n=] 斐波那契 [#
    [# 叼回来 1~ #] 好不好? n <= 1
    不然 [# 叼回来 扒[=n - 1=]斐波那契~ + 扒[=n - 2=]斐波那契~ #]~
#]~

扒[="The 5th term of the Fibonacci sequence is: ", 扒[=5=]斐波那契=]喵~

Factorial (Recursion)

想要 [=n=] 阶乘 [#
    [# 叼回来 1~ #] 好不好? n <= 1
    不然 [# 叼回来 n * 扒[=n - 1=]阶乘~ #]~
#]~

扒[="The factorial of 5 is: ", 扒[=5=]阶乘=]喵~

Number Guessing Game

想要 [==] 猜数字 [#
    蹭 答案~ 答案 就是 扒[=1, 100=]添乱~
    扒[="I'm thinking of a number between 1 and 100 meow~"=]喵~

    玩耍 [#
        蹭 输入 就是 扒[='Guess: '=]祈求~
        蹭猜测就是扒[=输入=]变摸数~ (Spaces between words are not necessary)

        [# 扒[="Please enter a number meow:"=]喵~ #] 好不好? 猜测 == 空碗
        不然 [#
            [# 扒[="Too small meow~"=]喵~ #] 好不好? 猜测 < 答案
            不然 [# 扒[="Too big meow~"=]喵~ #] 好不好? 猜测 > 答案
            不然 [#
                扒[="Correct! You are a genius cat meow~"=]喵~
                累了~
            #]~
        #]~
    #]~
#]~

扒[==]猜数字~

External resources

• Meaoiu on GitHub - The interpreter, parser, and language server API source code.
• Web Interpreter - Try Meaoiu online.