bump version (#6)

* add interactiveness to features, add keybindings to doc
* added commands

README.md

@@ -15,10 +15,13 @@ Features:
 - various stack manipulation commands
 - basic math operators
 - advanced math functions (not yet complete)
-- provides interactive repl
 - can be used on the commandline
 - can calculate data in batch mode (also from STDIN)
 - extensible with custom LUA functions
+- provides interactive repl
+- completion
+- history
+
 
 ## Working principle
 

calc.go

@@ -32,6 +32,7 @@ type Calc struct {
 	debug        bool
 	batch        bool
 	stdin        bool
+	showstack    bool
 	stack        *Stack
 	history      []string
 	completer    readline.AutoCompleter
@@ -48,6 +49,7 @@ type Calc struct {
 const Help string = `Available commands:
 batch                toggle batch mode
 debug                toggle debug output
+show                 show the last 5 items of the stack
 dump                 display the stack contents
 clear                clear the whole stack
 shift                remove the last element of the stack
@@ -81,7 +83,7 @@ median               median of all values`
 // commands, constants and operators,  defined here to feed completion
 // and our mode switch in Eval() dynamically
 const (
-	Commands  string = `dump reverse debug undebug clear batch shift undo help history manual exit quit swap`
+	Commands  string = `dump reverse debug undebug clear batch shift undo help history manual exit quit swap show`
 	Constants string = `Pi Phi Sqrt2 SqrtE SqrtPi SqrtPhi Ln2 Log2E Ln10 Log10E`
 )
 
@@ -162,14 +164,21 @@ func (c *Calc) ToggleStdin() {
 	c.stdin = !c.stdin
 }
 
+func (c *Calc) ToggleShow() {
+	c.showstack = !c.showstack
+}
+
 func (c *Calc) Prompt() string {
 	p := "\033[31m»\033[0m "
 	b := ""
+
 	if c.batch {
 		b = "->batch"
 	}
+
 	d := ""
 	v := ""
+
 	if c.debug {
 		d = "->debug"
 		v = fmt.Sprintf("/rev%d", c.stack.rev)
@@ -271,6 +280,8 @@ func (c *Calc) Eval(line string) {
 				for _, entry := range c.history {
 					fmt.Println(entry)
 				}
+			case "show":
+				c.ToggleShow()
 			case "exit":
 				fallthrough
 			case "quit":
@@ -282,6 +293,16 @@ func (c *Calc) Eval(line string) {
 			}
 		}
 	}
+
+	if c.showstack && !c.stdin {
+		dots := ""
+
+		if c.stack.Len() > 5 {
+			dots = "... "
+		}
+		last := c.stack.Last(5)
+		fmt.Printf("stack: %s%s\n", dots, list2str(last))
+	}
 }
 
 // Execute a math function, check if it is defined just in case

main.go

@@ -30,7 +30,7 @@ import (
 	lua "github.com/yuin/gopher-lua"
 )
 
-const VERSION string = "2.0.2"
+const VERSION string = "2.0.3"
 
 const Usage string = `This is rpn, a reverse polish notation calculator cli.
 
@@ -39,6 +39,7 @@ Usage: rpn [-bdvh] [<operator>]
 Options:
   -b, --batchmode   enable batch mode
   -d, --debug       enable debug mode
+  -s, --stack       show last 5 items of the stack (off by default)
   -m, --manual      show manual
   -v, --version     show version
   -h, --help        show help
@@ -58,6 +59,7 @@ func main() {
 	configfile := ""
 
 	flag.BoolVarP(&calc.batch, "batchmode", "b", false, "batch mode")
+	flag.BoolVarP(&calc.showstack, "showstack", "s", false, "show stack")
 	flag.BoolVarP(&enabledebug, "debug", "d", false, "debug mode")
 	flag.BoolVarP(&showversion, "version", "v", false, "show version")
 	flag.BoolVarP(&showhelp, "help", "h", false, "show usage")

rpn.go

@@ -111,7 +111,9 @@ DESCRIPTION
     switch or debug toggle command), then the backup stack is also being
     displayed.
 
-    The stack can be reversed using the reverse command.
+    The stack can be reversed using the reverse command. However, sometimes
+    only the last two values are in the wrong order. Use the swap command to
+    exchange them.
 
     You can use the shift command to remove the last number from the stack.
 
@@ -145,8 +147,52 @@ DESCRIPTION
         log10 log1p log2 logb pow round roundtoeven sin sinh tan tanh trunc y0
         y1 copysign dim hypot
 
+    Commands:
+
+        batch                toggle batch mode
+        debug                toggle debug output
+        dump                 display the stack contents
+        clear                clear the whole stack
+        shift                remove the last element of the stack
+        reverse              reverse the stack elements
+        swap                 exchange the last two stack elements
+        show                 show the last 5 items of the stack
+        history              display calculation history
+        help|?               show this message
+        quit|exit|c-d|c-c    exit program
+
     Refer to https://pkg.go.dev/math for details about those functions.
 
+INTERACTIVE REPL
+    While you can use rpn in the command-line, the best experience you'll
+    have is the interactive repl (read eval print loop). Just execute "rpn"
+    and you'll be there.
+
+    In interactive mode you can use TAB completion to complete commands,
+    operators and functions. There's also a history, which allows you to
+    repeat complicated calculations (as long as you've entered them in one
+    line).
+
+    There are also a lot of key bindings, here are the most important ones:
+
+    ctrl-c + ctrl-d
+        Exit interactive rpn
+
+    ctrl-z
+        Send rpn to the backgound.
+
+    ctrl-a
+        Beginning of line.
+
+    ctrl-e
+        End of line.
+
+    ctrl-l
+        Clear the screen.
+
+    ctrl-r
+        Search through history.
+
 EXTENDING RPN USING LUA
     You can use a lua script with lua functions to extend the calculator. By
     default the tool looks for "~/.rpn.lua". You can also specify a script

rpn.pod

@@ -154,8 +154,65 @@ Math functions:
     log10 log1p log2 logb pow round roundtoeven sin sinh tan tanh trunc y0
     y1 copysign dim hypot
 
+Commands:
+
+    batch                toggle batch mode
+    debug                toggle debug output
+    dump                 display the stack contents
+    clear                clear the whole stack
+    shift                remove the last element of the stack
+    reverse              reverse the stack elements
+    swap                 exchange the last two stack elements
+    show                 show the last 5 items of the stack
+    history              display calculation history
+    help|?               show this message
+    quit|exit|c-d|c-c    exit program
+
+
 Refer to https://pkg.go.dev/math for details about those functions.
 
+=head1 INTERACTIVE REPL
+
+While you can use rpn in the command-line, the best experience you'll
+have is the interactive repl (read eval print loop). Just execute
+C<rpn> and you'll be there.
+
+In interactive mode you can use TAB completion to complete commands,
+operators and functions. There's also a history, which allows you to
+repeat complicated calculations (as long as you've entered them in one
+line).
+
+There are also a lot of key bindings, here are the most important
+ones:
+
+=over
+
+=item ctrl-c + ctrl-d
+
+Exit interactive rpn
+
+=item ctrl-z
+
+Send rpn to the backgound.
+
+=item ctrl-a
+
+Beginning of line.
+
+=item ctrl-e
+
+End of line.
+
+=item ctrl-l
+
+Clear the screen.
+
+=item ctrl-r
+
+Search through history.
+
+=back
+
 =head1 EXTENDING RPN USING LUA
 
 You can use a lua script with lua functions to extend the