Basic Syntax

SFX uses a clean, readable syntax inspired by natural language. This chapter covers the fundamental syntax rules.

Program Structure

Every SFX program has a Story block - the main entry point:

Story:
    Print "Hello, SFX!"

A complete program can include:

• Concepts - Classes/objects (defined before Story)
• Situations - Context modifiers (defined before Story)
• Story - Main entry point (required)

# Complete program structure
Concept: MyClass
    Field1, Field2

Situation: MyContext
    Adjust MyClass:
        # Adjustments here

Story:
    # Main program code here
    Print "Starting program..."

Indentation

SFX uses significant indentation like Python:

• Use 4 spaces per indentation level
• DO NOT use tabs (use spaces only)
• Consistent indentation defines code blocks

Story:
    If True:
        Print "This is indented"
        Print "So is this"
    Print "Back to outer level"

Comments

Use # for single-line comments:

# This is a comment
Story:
    Print "Hello"  # Inline comment
    # Another comment

Note: SFX currently supports only single-line comments. Multi-line comments are not yet supported.

Statements

Statements in SFX typically end at the end of the line:

Story:
    Name is "Alice"
    Age is 25
    Print Name

Keywords

SFX uses descriptive English keywords:

Case Sensitivity

SFX keywords are case-sensitive:

Story:
    # Correct
    Print "Hello"

    # Wrong (will cause error)
    print "Hello"  # lowercase 'p'
    PRINT "Hello"  # uppercase

Variable and concept names are also case-sensitive:

Story:
    Name is "Alice"
    name is "Bob"
    # 'Name' and 'name' are different variables

Line Continuation

Long statements can be continued on the next line within certain contexts:

# Lists and maps can span multiple lines
Items is [
    "Item 1",
    "Item 2",
    "Item 3"
]

User is {
    name: "Alice",
    age: 30,
    email: "alice@example.com"
}

Naming Conventions

Variables and Fields

Use PascalCase for variable and field names:

Story:
    FirstName is "Alice"
    LastName is "Smith"
    UserAge is 25
    IsActive is True

Concepts

Use PascalCase for concept names:

Concept: Person
Concept: ShoppingCart
Concept: HttpClient

Methods

Use PascalCase for method names:

Concept: Calculator
    To Add with X and Y:
        Return X + Y

    To CalculateTotal:
        # Method code

Situations

Use PascalCase for situation names:

Situation: AdminMode
Situation: DebugMode
Situation: VIPCustomer

Best Practices

1. Use Descriptive Names

# Good
UserName is "Alice"
ShoppingCart is []
TotalPrice is 99.99

# Less clear
UN is "Alice"
SC is []
TP is 99.99

2. Keep Indentation Consistent

# Good
Story:
    If Condition:
        DoSomething()
        DoSomethingElse()

# Bad (inconsistent indentation)
Story:
    If Condition:
      DoSomething()
        DoSomethingElse()  # Error!

3. One Statement Per Line

# Good
Name is "Alice"
Age is 25

# Possible but discouraged
Name is "Alice", Age is 25  # Works only with Set statements

4. Group Related Code

Story:
    # Configuration
    Host is "localhost"
    Port is 8080

    # User setup
    Create User Called Admin
    Set Admin.Name to "Administrator"
    Set Admin.Role to "admin"

    # Start server
    Server.Start with Host and Port

5. Use Comments for Clarity

Story:
    # Calculate tax (10% rate)
    Price is 100
    Tax is Price * 0.1
    Total is Price + Tax

    # Display result
    Print "Total with tax: $" + Total

Example: Complete Program

# User Management System

Concept: User
    Name, Email, Role, IsActive

    To Activate:
        Set This.IsActive to True
        Print This.Name + " has been activated"

    To Deactivate:
        Set This.IsActive to False
        Print This.Name + " has been deactivated"

    To UpdateEmail with NewEmail:
        Set This.Email to NewEmail
        Print "Email updated to: " + NewEmail

Situation: AdminMode
    Adjust User:
        To UpdateEmail with NewEmail:
            # Admin can force update
            Set This.Email to NewEmail
            Print "[ADMIN] Email forcefully updated to: " + NewEmail

Story:
    # Create users
    Create User Called Alice
    Set Alice.Name to "Alice Smith"
    Set Alice.Email to "alice@example.com"
    Set Alice.Role to "user"
    Set Alice.IsActive to True

    Create User Called Bob
    Set Bob.Name to "Bob Jones"
    Set Bob.Email to "bob@example.com"
    Set Bob.Role to "admin"
    Set Bob.IsActive to False

    # Activate Bob
    Bob.Activate

    # Update Alice's email
    Alice.UpdateEmail with "alice.smith@example.com"

    # Admin mode - force update
    Switch on AdminMode
    Bob.UpdateEmail with "admin@example.com"
    Switch off AdminMode

    Print "=== User Summary ==="
    Print Alice.Name + " - " + Alice.Email + " (Active: " + Alice.IsActive + ")"
    Print Bob.Name + " - " + Bob.Email + " (Active: " + Bob.IsActive + ")"

What’s Next?

Now that you understand the basics, learn about:

• Variables and Assignment - How to work with variables
• Data Types - Numbers, strings, lists, maps, and more
• Operators - Arithmetic, comparison, logical operators
• Comments - Documenting your code
• Control Flow - Making decisions and loops