Language Reference

This section provides a comprehensive reference for the Flexa programming language. It covers the syntax, rules, and features of Flexa in a concise and organized manner. Use this guide as a quick reference while writing Flexa code.

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Table of Contents

1. Program Structure
2. Variables and Constants
3. Data Types
4. Operators
5. Control Structures
6. Functions
7. Structs
8. Arrays
9. Error Handling
10. Built-in Functions
11. Built-in Libraries

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Program Structure

A Flexa program consists of:

• Namespace declaration (optional)
• Library imports (optional)
• Namespace includes/excludes (optional)
• Function and variable declarations
• Executable code

Example

namespace my_program;

using flx.core.console;

include namespace flx;

fun main() {
  println("Hello, Flexa!");
}

main();

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Variables and Constants

Variables

var name: type = value;

• Example: var age: int = 25;

Constants

const name: type = value;

• Example: const PI: float = 3.14;

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Data Types

Primitive Types

• bool: true or false
• int: Integer numbers (e.g., 42)
• float: Floating-point numbers (e.g., 3.14)
• char: Single character (e.g., 'a')
• string: Sequence of characters (e.g., "Hello")

Composite Types

• Arrays: int[], string[], etc.
• Structs: User-defined types.

Special Types

• function: Represents a function or lambda.
• void: Represents the absence of a value.
• any: Represents a value of any type.

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Operators

Value Reference Operators

• ref, unref

Increment Operators

• ++, --

Ternary Operator

• expression ? if_true_expression : if_false_expression

Arithmetic Operators

• +, -, *, /, %, ** (exponentiation), /% (floor division)

Comparison Operators

• ==, !=, <, >, <=, >=, <=> (three-way)

Logical Operators

• and, or, not

Bitwise Operators

• &, |, ^, ~, <<, >>

Assignment Operators

• =, +=, -=, *=, /=, %=, **=, &=, |=, ^=, <<=, >>=

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Control Structures

Conditionals

• if, else, else if, switch

Loops

• while, do-while, for, foreach

Flow Control

• break, continue, return, exit

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Functions

Function Declaration

fun name(parameter: type, ...): return_type {
  // Function body
}

Lambda Functions

var lambda: function = fun (parameter: type, ...): return_type {
  // Function body
};

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Structs

Struct Declaration

struct Name {
  var field1: type;
  var field2: type;
}

Struct Instance

var instance: Name = Name{field1=value1, field2=value2};

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Arrays

Array Declaration

var array[]: type = {value1, value2, ...};

Array Access

var element = array[index];

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Error Handling

Try-Catch

try {
  // Code that may throw an exception
} catch (var error) {
  // Handle the exception
}

Throw

throw string_expression;
// or
throw Exception{error=string_expression};

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Built-in Functions

• print(optional_message): Prints a message to the console.
• println(optional_message): Prints a message to the console with a newline.
• read(optional_message): Reads a line of input from the console.
• readch(): Reads a single character from the console.
• len(value): Returns the length of a string or array.
• sleep(milliseconds): Pauses the program for a specified time.
• system(command): Executes a system command.

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Built-in Libraries

Flexa provides a rich set of built-in libraries for tasks like file handling, networking, and data manipulation. Some of the key libraries include:

• flx.core.console: Console input/output.
• flx.core.files: File operations.
• flx.core.HTTP: HTTP communication.
• flx.std.math: Mathematical functions.
• flx.std.strings: String manipulation.

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What’s Next?

If you have questions or run into issues while using Flexa, check out the FAQ and Common Issues section for solutions and tips.

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Next: FAQ and Common Issues →