Lexical Structure

Comments

Cesium supports three types of comments:

// Single-line comment
 
/*
  Multi-line comment
*/
 
/**
 * Documentation comment for functions
 * @param x The input parameter
 * @return The computed result
 */
i32 = documented_function(i32 x) {
    // implementation
}

Keywords

Cesium reserves the following keywords:

Core Types: file, str, list, dict, slice, struct, path, uword

Language Constructs: alias, catch, as, return, comptime, generic, sizeof, typeof, asm, void, enum, error, null, union

Control Flow: if, while, for, else, do, with, defer, break, continue, switch, case, fallthrough, throw

Function Qualifiers: operator, context, property, private, secret, static, destruct

Variable Qualifiers: const, static, private, secret, volatile, atomic, register, simd

C Interop: extern, export

OOP Constructs: trait, impl, type, this, super

Namespacing: std, namespace

Built-in Functions and Constants

Memory Management: alloc(), free(), realloc()

Debugging and I/O: printf(), debugf(), assert(), stdout, stdin, stderr

Mathematical: floor(), ceil(), trunc(), round(), trueround(), abs(), min(), max(), mean(), norm(), pi

Identifiers

Identifiers follow C-style rules: start with letter or underscore, followed by letters, digits, or underscores.

Valid identifiers:

variable_name
_private_var
Class2D
MAX_SIZE

String Literals and Interpolation

Cesium supports multiple string literal formats:

str simple = "Hello, world!";
str interpolated = `Hello, {name}! You have {count} messages.`;
path file_path = path(`{home_dir}/config/settings.conf`);

String Types

Simple strings use double quotes and support escape sequences
Interpolated strings use backticks and allow expression embedding with {}
Path strings are a special type for filesystem paths with automatic normalization

Cesium

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