Spec Update: Batch 09 — Generics, Closures, Option/Result

Date: 2026-04-16 Plans Referenced: Plan 048 (generics), Plan 049 (operators), Plan 052 (List/storage), Plan 057 (generic specs), Plan 059 (generic ext), Plan 060 (closures), Plan 120 (Option/Result), Plan 165 (struct patterns) Source Files: ast/types.rs (GenericParam, TypeParam, ConstParam), ast/fun.rs (Closure, ClosureParam), ast.rs (Option/Result expr variants) Sections Updated: Generics (Section 14 — NEW), Closures (Section 15 — NEW), Option and Result (Section 16 — NEW)

Old Content

No dedicated sections for generics, closures, or Option/Result existed. These features were partially documented in Functions section or not at all.

New Content

Generics (Section 14)

• Type parameters: <T>
• Const parameters: <N u32> with default values
• Generic constraints: <T has Comparable>
• Monomorphization for C/Rust backends

Closures (Section 15)

• Syntax forms: no-params => expr, single x => expr, multi (a, b) => expr
• Typed closures: (a int, b int) => int { ... }
• Capture semantics: view (default) vs move
• Iterator usage with .map(), .filter()

Option and Result (Section 16)

• ?T (Option): Some(T) or None
• !T (Result): Ok(T) or Err(message)
• Constructors: Some, None, Ok, Err
• Null coalescing: ??
• Error propagation: .?
• Pattern matching

Notes

• Closures use => syntax, NOT Rust's |...| syntax
• ?T is syntactic sugar for Option<T>, !T for Result<T> (or Result<T, E>)
• GenericParam enum has two variants: Type (TypeParam) and Const (ConstParam)
• ConstParam supports default values: N u32 = 64