dart-use-pattern-matching

Contents

• Pattern Selection Strategy
• Switch Expressions vs Switch Statements
• Core Pattern Syntaxes
• Workflow: Designing Pattern Matching Logic
• Examples

Pattern Selection Strategy

Apply distinct pattern matching strategies based on the target data structure:

• JSON Validation and Destructuring: Use Map and List patterns to simultaneously validate nested shapes and bind values to local variables in a single step.
• Multiple Returns: Return Records from functions and use Record patterns to destructure named or positional values directly into scoped variables.
• Algebraic Data Types (ADTs): Combine sealed class hierarchies with Object patterns in switch expressions to benefit from compile-time exhaustiveness checking.
• Numeric Ranges and logical Checks: Combine relational patterns (>=, <, etc.) and logical-and (&&) or logical-or (||) operators within switch cases.
• Guard Clauses: Use the when keyword to assert dynamic conditions that cannot be expressed purely through static patterns.

Switch Expressions vs Switch Statements