Chotulang Interpreter

This is the official interpreter for the Chotulang programming language.

Installation

pip install chotulang

Basic syntax

========================================== CHOTULANG DEVELOPMENT GUIDE (Version 2.5.1)

Chotulang is a dynamic, Python-compatible language that emphasizes clean, readable syntax and supports powerful functional features like pipes and lambdas.

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MODULE 1: CORE FUNDAMENTALS

1. PRINTING AND VARIABLES Use 'out' to print. Use 'var' to declare a variable.

var name = "Alex" // String var count = 5 // Number var is_active = true // Boolean

out "Hello,", name, "!" out "The value is:", count

// User Input out "Enter a number:" var user_input = ask() // Reads a line of text out "You entered:", user_input

2. COMMENTS Use the '#' symbol for comments.

This line is ignored by the interpreter

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MODULE 2: OPERATOR PRECEDENCE

Understanding the order of operations ensures your calculations are correct.

Precedence	Operator	Description	Example
Highest	()	Parentheses (Forces order)	(5 + 2) * 3
2	**	Power/Exponent (Right-associative)	2 ** 3 ** 2 is 2 ** (3 ** 2) (512)
3	*, /, %	Multiplication, Division, Modulo	10 / 2 * 5 (Left-to-right)
4	+, -	Addition, Subtraction	3 + 4 - 1 (Left-to-right)
5	<, >, ==, !=	Comparison	x > 5
6	&&,
Lowest	=, +=, -=, *=, /=	Assignment	x = 10

// Power Operator Example (Exponent) var result_power = 8 ** 2 out "8 squared is:", result_power // 64

var complex_calc = 10 - 2 ** 3 * 2 // Order: 2**3 (8), then 8*2 (16), then 10-16 (-6) out "Complex calculation:", complex_calc

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MODULE 3: CONTROL FLOW & LOOP JUMPS

1. IF/ELSE STATEMENTS Conditional execution blocks. The curly braces {} are mandatory.

var temperature = 30

if temperature > 25 { out "It is hot." } else { out "It is mild." }

2. LOOPS (ITERATION)

// The 'do' Loop (Similar to While) var i = 0 do i < 3 { out "Do loop iteration:", i i += 1 }

// The 'for' Loop (Iterates over a list or range) for number in 0..4 { out "Current number:", number }

3. LOOP JUMP STATEMENTS

// WARNING: These must only be used inside a 'do' or 'for' loop!

// 'break' // Stops the current loop entirely and execution continues after the loop. do true { out "Running once..." break // Exits the 'do' loop }

// 'next' // Skips the rest of the code in the current loop body and starts the next iteration. for i in 1..5 { if i == 3 { next // Skip printing 3, go straight to 4 } out "Number:", i }

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MODULE 4: DATA STRUCTURES

1. LISTS (Ordered Collections)

var fruits = ["apple", "banana", "kiwi"] out fruits[1] // Access: banana fruits.append("grape") // Add to end

2. DICTIONARIES (Key-Value Pairs)

var user = { "id": 101, "status": "online" }

out user["status"] // Access: online user.set("city", "London") // Add/Update a key

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MODULE 5: FUNCTIONS AND PIPES

1. STANDARD FUNCTIONS ('fn') Use 'fn' for reusable code blocks. Use 'ret' to return a value.

fn multiply(x, y) { ret x * y }

var product = multiply(8, 6) out "Product:", product

2. LAMBDA FUNCTIONS (Anonymous Functions)

// Syntax: fn(params) => expression var is_even = fn(n) => n % 2 == 0 out is_even(4) // true

3. THE PIPE OPERATOR (|>) Pass the result of one expression as the first argument to the next function.

fn increment(x) { ret x + 1 } fn double(x) { ret x * 2 }

var value = 10 |> increment |> double // (10 + 1) * 2 = 22 out value

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MODULE 6: COMPLEX MATHEMATICAL OPERATIONS

1. USING THE PYTHON MATH LIBRARY Import the standard Python 'math' module using the 'use' keyword.

use math

// Square Root var root = math.sqrt(64) out "Root of 64:", root

// Trigonometry and Constants var angle = math.radians(45) var sine_val = math.sin(angle) out "Sine of 45 deg:", sine_val out "Pi value:", math.pi // Access constant

2. COMPLEX CALCULATION WITH PIPES

fn area_calc(r) { ret math.pi * r ** 2 } // Using ** for r squared fn round_2(n) { ret round(n, 2) }

var r = 5 var final_area = r |> area_calc |> round_2 // 5 -> area_calc -> round_2 out "Rounded Area:", final_area

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PRACTICE PROJECTS

1. THE GUESSING GAME Use the 'random' library (use random). Generate a random number. Use a 'do' loop and 'if/else' to let the user guess until correct, providing 'Too High' or 'Too Low' hints.

2. MATH & DATA PIPELINE Create a list of numbers. Use map (or a loop) and a lambda to cube every number, then use the pipe operator to feed the resulting list to a function that calculates the sum of all elements.

3. GEOMETRY FUNCTION Write a function that accepts two numbers (A and B). This function must check if A and B are positive numbers. If they are, it uses the 'math' library to calculate the perimeter of a rectangle (2A + 2B) and returns it. If not, it returns the string "Error: Invalid dimensions".