auto reference for typed CompositeLit

[xushiwei]

In most cases, when a struct T is passed as an argument to a function f, it is typically passed as a pointer (*T), i.e., f &T{...}. We hope that when passing a typed CompositeLit (such as T{...}) to function f, it can automatically reference the CompositeLit. That is, f T{...} is equivalent to f &T{...}.

[xushiwei]

/code

[xgopilot]

Implementation Complete ✓

Successfully implemented auto-reference for typed CompositeLit as requested in #2484.

Changes Made

Modified Files:

• cl/expr.go: Enhanced compileCompositeLitEx() to automatically reference typed composite literals when passed to functions expecting pointer parameters

New Files:

• cl/_testgop/autoref-2484/in.xgo: Test input with examples for struct, slice, map, and array
• cl/_testgop/autoref-2484/out.go: Expected output showing auto-referencing behavior

How It Works

When you pass a typed composite literal to a function expecting a pointer, XGo now automatically adds the & operator:

// Before: Required explicit &
processPerson(&Person{Name: "Alice", Age: 30})

// Now: Both syntaxes work!
processPerson(Person{Name: "Alice", Age: 30})   // auto-referenced
processPerson(&Person{Name: "Alice", Age: 30})  // still works

This works for all composite literal types:

• Structs: Person{...} → &Person{...}
• Slices: []int{1,2,3} → &[]int{1,2,3}
• Maps: map[string]int{"a":1} → &map[string]int{"a":1}
• Arrays: [3]int{1,2,3} → &[3]int{1,2,3}

Testing

• ✓ All existing tests pass
• ✓ New comprehensive test cases added and passing
• ✓ Code formatted with go fmt

Pull Request

Created PR #2485: #2485

The implementation follows the XGo project guidelines (Phase 2: Semantic Implementation) and maintains full backward compatibility with existing code.