Method generateArmsChain

pkg/codegen/match.go:308–348

generateArmsChain generates an if/else chain for a group of arms. This handles multiple patterns for the same constructor with guards.

(arms []*ast.MatchArm)

// generateArmsChain generates an if/else chain for a group of arms.
// This handles multiple patterns for the same constructor with guards.
func (g *MatchCodeGen) generateArmsChain(arms []*ast.MatchArm) {
	for i, arm := range arms {
		hasGuard := arm.Guard != nil
		isFirst := i == 0
		isLast := i == len(arms)-1

		if hasGuard {
			guardResult := GenerateExpr(arm.Guard)

			if isFirst {
				g.Write("if " + string(guardResult.Output) + " {\n")
			} else {
				g.Write("} else if " + string(guardResult.Output) + " {\n")
			}
		} else {
			// Unguarded arm
			if !isFirst {
				// This is the else fallback after guarded arms
				g.Write("} else {\n")
			}
			// If first and unguarded, no wrapper needed (direct code in case)
		}

		// Generate body
		bodyResult := GenerateExpr(arm.Body)
		// Check if body is already a return statement (ReturnExpr)
		_, isReturnExpr := arm.Body.(*ast.ReturnExpr)
		if g.Match.IsExpr && !isReturnExpr {
			// Only prepend "return" if body is not already a return statement
			g.Write("return " + string(bodyResult.Output) + "\n")
		} else {
			g.Buf.Write(bodyResult.Output)
			g.WriteByte('\n')
		}

		// Close if/else if last arm has guard or previous arms had guards
		if isLast && (hasGuard || i > 0 && arms[0].Guard != nil) {
			g.Write("}\n")
		}
	}
}

// generateGroupedCasesWithAssignment is like generateGroupedCases but for assignment context.
func (g *MatchCodeGen) generateGroupedCasesWithAssignment(varName string, typeSwitch bool) {