diff options
| -rw-r--r-- | internal/repl/handlers.go | 40 | ||||
| -rw-r--r-- | internal/repl/repl.go | 10 |
2 files changed, 38 insertions, 12 deletions
diff --git a/internal/repl/handlers.go b/internal/repl/handlers.go index c2f8af5..069e945 100644 --- a/internal/repl/handlers.go +++ b/internal/repl/handlers.go @@ -12,6 +12,20 @@ import ( "codeberg.org/snonux/gt/internal/rpn" ) +// RPNCalculator defines the methods needed by REPL handlers to interact with +// the RPN engine. By depending on this interface instead of the concrete *rpn.RPN, +// handlers obey DIP and the Law of Demeter. +type RPNCalculator interface { + ParseAndEvaluate(string) (string, error) + EvalOperator(string) (string, error) + GetCurrentStack() []rpn.StackValue + SetCurrentStack([]rpn.StackValue) + SetMode(rpn.CalculationMode) + GetMode() rpn.CalculationMode + IsStandardOperator(string) bool + IsHyperOperator(string) bool +} + // CommandHandler represents a handler in the chain of responsibility pattern. // Each handler can process a command or pass it to the next handler in the chain. // @@ -104,21 +118,21 @@ func handleRatCommand(repl *REPL, input string) (string, bool, error) { } modeArg := strings.ToLower(args[1]) - rpnCalc := repl.rpnState.rpnCalc + calc := repl.RpnCalculator() switch modeArg { case "on": - rpnCalc.SetMode(rpn.RationalMode) + calc.SetMode(rpn.RationalMode) return "Rational mode enabled", true, nil case "off": - rpnCalc.SetMode(rpn.FloatMode) + calc.SetMode(rpn.FloatMode) return "Rational mode disabled (using float64)", true, nil case "toggle": - if rpnCalc.GetMode() == rpn.FloatMode { - rpnCalc.SetMode(rpn.RationalMode) + if calc.GetMode() == rpn.FloatMode { + calc.SetMode(rpn.RationalMode) return "Rational mode enabled", true, nil } else { - rpnCalc.SetMode(rpn.FloatMode) + calc.SetMode(rpn.FloatMode) return "Rational mode disabled (using float64)", true, nil } default: @@ -136,10 +150,11 @@ type RPNHandler struct { // evalWithStackRestore evaluates an RPN expression, restoring the stack on error // so that a failed parse never corrupts the user's stack. func (h *RPNHandler) evalWithStackRestore(repl *REPL, input string) (string, error) { - savedStack := repl.rpnState.rpnCalc.GetCurrentStack() - result, err := repl.rpnState.rpnCalc.ParseAndEvaluate(input) + calc := repl.RpnCalculator() + savedStack := calc.GetCurrentStack() + result, err := calc.ParseAndEvaluate(input) if err != nil { - repl.rpnState.rpnCalc.SetCurrentStack(savedStack) + calc.SetCurrentStack(savedStack) return "", err } return result, nil @@ -173,7 +188,8 @@ func (h *RPNHandler) Handle(repl *REPL, input string) (output string, handled bo } // Try RPN parsing first (for bare RPN expressions like "3 4 +") - if repl.rpnState != nil { + calc := repl.RpnCalculator() + if calc != nil { // Check if input looks like RPN (contains spaces or is a single known operator) if strings.Contains(input, " ") { result, err := h.evalWithStackRestore(repl, input) @@ -188,8 +204,8 @@ func (h *RPNHandler) Handle(repl *REPL, input string) (output string, handled bo if len(fields) == 1 { token := fields[0] op := strings.ToLower(token) - if repl.rpnState.rpnCalc.IsStandardOperator(op) || repl.rpnState.rpnCalc.IsHyperOperator(op) { - result, err := repl.rpnState.rpnCalc.EvalOperator(op) + if calc.IsStandardOperator(op) || calc.IsHyperOperator(op) { + result, err := calc.EvalOperator(op) if err != nil { return "", true, err } diff --git a/internal/repl/repl.go b/internal/repl/repl.go index 98ff23e..2ecd9ea 100644 --- a/internal/repl/repl.go +++ b/internal/repl/repl.go @@ -87,6 +87,16 @@ type REPL struct { logWriter io.WriteCloser } +// RpnCalculator returns the RPN calculator behind this REPL as an interface. +// This lets handlers depend on the RPNCalculator interface (DIP) rather than +// reaching through repl.rpnState.rpnCalc into concrete types. +func (r *REPL) RpnCalculator() RPNCalculator { + if r.rpnState == nil { + return nil + } + return r.rpnState.rpnCalc +} + // ReadlinePrompt provides an interactive prompt using chzyer/readline. // It supports: // - Ctrl+R for reverse history search |