STYLE-GUIDE.md

Style Guide

Core Principles

1. Use C-style Braces

• Always use braces for control structures, even for single-line blocks
• Opening brace on the same line
• Closing brace on its own line

// Good
if (condition) {
  doSomething()
} else {
  doSomethingElse()
}

// Bad - No braces
if (condition)
  doSomething()

// Bad - Indentation-based syntax
if (condition)
  doSomething()
  andThenThis()  // Unclear scope

2. No Indentation-Based Syntax

• Do not rely on indentation for scope
• Always use explicit braces to define scope

// Good
def method() = {
  val result = {
    val x = compute()
    transform(x)
  }
  result
}

// Bad - Indentation-based
def method() =
  val result =
    val x = compute()
    transform(x)
  result

3. Function Definitions

• Opening brace on the same line as the function definition
• Use explicit return types

// Good
def process(input: String): Result = {
  // implementation
}

// Bad
def process(input: String): Result = 
  // implementation

4. Pattern Matching

• Use braces for case blocks
• Align case statements

// Good
expr match {
  case Literal(value) => {
    process(value)
  }
  case Identifier(name) => {
    lookup(name)
  }
}

// Bad
expr match
  case Literal(value) =>
    process(value)
  case Identifier(name) =>
    lookup(name)

5. For Comprehensions

• Use braces instead of indentation

// Good
for {
  x <- xs
  y <- ys
} yield {
  combine(x, y)
}

// Bad
for
  x <- xs
  y <- ys
yield combine(x, y)

Additional Guidelines

• Use parentheses for method calls even when they could be omitted
• Prefer multi-line formatting with braces for complex expressions
• Use explicit type annotations for public APIs
• Keep line length reasonable (max 120 characters)
• Use two-space indentation within braces