X-Git-Url: http://git.shiar.nl/descalc.git/blobdiff_plain/ca2e1ff106e7e71cca06067106f500313b18e669..905da7ac2077425ebb7ed7507f2ae8d00f4a5beb:/sdc.pl

diff --git a/sdc.pl b/sdc.pl
old mode 100644
new mode 100755
index c6a82af..f1692ed
--- a/sdc.pl
+++ b/sdc.pl
@@ -1,79 +1,68 @@
 #!/usr/bin/perl
 
-### curses rpn desktop calculator ###
-
+### SDC - small desktop calculator ###
+# reverse polish notition calculator using curses
 # by Shiar <shiar.org>
 
-# 06-18       - start
-# 06-25       -
-# 08-04 14:45 - error dialog (don't mess up screen)
+# 1.01 06-18       - start
+# 1.03 06-25       -
+# 1.04 08-04 14:45 - error dialog (don't mess up screen)
+# 1.05 09-10 19:45 - hp48-like drop (backspace but not editing value)
+#                  - argument checking
+#                  - command backspacing
+# 1.06 09-15 23:10 - menu contents in module
+#                  - new commands: a?(sin|cos|tan)h, inv, !, rand
+#                  - x and v shortkeys
+# 1.07 09-24 23:50 - numeric modifiers hardcoded instead of in action hash
+#                  - action undo: last stack alteration can be undone
+#                  - enter on no value repeats last val on stack
+#                  - new commands: sr/sr, shortkeys ( )
 
 use strict;
 use warnings;
+use utf8;
 
 use Term::ReadKey;
 use Curses;
+use SDC::Menu 1.006;
 
 initscr;
-ReadMode 3;
+ReadMode 3;  # cbreak mode
+END {
+	ReadMode 0;
+	endwin;
+} # restore terminal on quit
 
-my $height = $LINES-3 || 4;
-my $width = $COLS || 42;
+my $height = $LINES<3 ? 4 : $LINES-3;  # stack depth (lines of stack plus one)
+my $width = $COLS || 42;  # limit value precision, stetch menu
 
-my @val = (0, 0); # val, frac
-my $nopush = 1; # 0=push and reset next; 1=reset next; 2=do nothing
+my %val = qw(i 0  frac 0);  # i, frac
 my @stack;
 my %var;
 my @menu;
+my $menumin;
 my %set = (
-	base  => 10,
-	numb  => 0, # fixed scientific engineering
-	card  => 1, # degrees radians grades
-	coord => 0, # cartesian polar spherical
-	complex => 0, # real complex
+	base     => 10,
+	numb     =>  0,  # fixed scientific engineering
+	card     =>  1,  # degrees radians grades
+	coord    =>  0,  # cartesian polar spherical
+	complex  =>  0,  # real complex
 	menushow => 12,
 ); # %set
 
-my @menus = (
-	[qw(quit base>1 math>8 mode>7)],
-	[qw(main>0 dec bin oct hex logic>3 bit>4)], #1 base
-	[qw(main>0 log alog ln exp sin cos tan 0 asin acos atan)], #2 math
-	[qw(base>1 and or xor not)], #3 base logic
-	[qw(base>1 rl sl asr sr rr)], #4 base bit
-	[qw(base>1 rlb slb srb rrb)], #5 base byte
-	[qw(main>0 sq sqrt ^ xroot)], #6
-	[qw(main>0 number_format angle_measure coord_system)], #7 mode
-	[qw(main>0
-		vector> matrix> list> hyperbolic>9 real>10 base>1
-		probability> fft> complex> constants>
-	)], #8 math
-	[qw(math>8
-		sinh cosh tanh asinh acosh atanh
-		expm lnp1
-	)], #9 math hyperbolic
-	[qw(math>8
-		% %ch %t min max mod
-		abs sign mant xpon ip fp
-		rnd trnc floor ceil r>d d>r
-	)], #10 math real
-	[qw(main>0
-		tools> length> area> volume> time> speed>
-		mass> force> energy> power> pressure> temperature>
-		electric_current> angle> light> radiation> viscosity>
-	)], #11 units
-); # @menus
 @menu = @{$menus[0]};
+$menumin = 0;
 
 my %falias = (
 	"\033"                         =>  0, # esc
 	"\033\117\120"                 =>  1, # f1
 	"\033\133\061\061\176"         =>  1, # f1
-	"\033\117\121"                 =>  2, # f2
 	"\033\133\061\062\176"         =>  2, # f2
-	"\033\117\122"                 =>  3, # f3
 	"\033\133\061\063\176"         =>  3, # f3
-	"\033\117\123"                 =>  4, # f4
 	"\033\133\061\064\176"         =>  4, # f4
+	"\033\117\121"                 =>  2, # f2
+	"\033\117\122"                 =>  3, # f3
+	"\033\117\123"                 =>  4, # f4
 	"\033\133\061\065\176"         =>  5, # f5
 	"\033\133\061\067\176"         =>  6, # f6
 	"\033\133\061\070\176"         =>  7, # f7
@@ -96,129 +85,190 @@ my %falias = (
 
 my %alias = (
 	chr 4 => 'quit', # ^D
-	'q' => 'quit', # quit
-	'_' => 'chs', # change sign
-	'e' => 'eex', # exponent
-	"\033\133\062\176" => 'swap', # ins
-	chr(27).chr(91).chr(51).chr(126) => 'clx', # del
-	chr 127 => '<-', # backspace
-	chr 8 => '<-', # backspace
-	"\014" => 'refresh', # ^L
-	"\033\133\110" => 'refresh', # home
+	chr 9 => 'more', # tab
+	'_'   => 'chs', # change sign; 48: y
+	'e'   => 'eex', # exponent; 48: z
+	"\033\133\062\176" => 'eex', # ins
+	"\033\133\063\176" => "clear", # del
+	chr 127 => 'drop', # backspace
+	chr 8   => 'drop', # backspace
+	chr 13  => 'enter', # enter
+	' '     => 'enter', # space
+	"\014"  => 'refresh', # ^L
+#	"\033\133\110" => 'refresh', # home
+
+#	"\033\133\101" => '', # up; 48: k (stack)
+	"\033\133\104" => 'undo', # left; 48: p (picture)
+#	"\033\133\102" => '', # down; 48: q (view)
+	"\033\133\103" => 'swap', # right; 48: r (swap)
 
 	'&' => 'and',
 	'|' => 'or',
 	'#' => 'xor',
 	'~' => 'not',
-
-	        's' => 'sin',
-	chr(27).'s' => 'asin',
-	        'u' => 'cos',
-	chr(27).'u' => 'acos',
-	        't' => 'tan',
-	chr(27).'t' => 'atan',
-	        'l' => 'log',
-	chr(27).'l' => 'alog',
-	        'n' => 'ln',
-	chr(27).'n' => 'exp',
-	        'x' => 'xroot',
-
+	'(' => 'sl',
+	')' => 'sr',
+
+	    "s" => "sin",
+	"\033s" => "asin",
+	    "c" => "cos",
+	"\033c" => "acos",
+	    "t" => "tan",
+	"\033t" => "atan",
+	    "l" => "log",
+	"\033l" => "alog",
+	    "n" => "ln",
+	"\033n" => "exp",
+	    "q" => "sq",
+	"\033q" => "sqrt",
+	    "x" => "^",
+	"\033x" => "xroot",
+	"\033^" => "xroot",
+	    "v" => "inv",
 ); # %alias
 
+=cut
+HP48 keys:
+    S     T     U      V     W     X
+ -  sin   cos   tan    sqrt  ^     1/x
+ <  asin  acos  atan   sq    alog  exp
+ >  [a]   ∫     ∑      xroot log   ln
+=cut
+
 my %action = (
-#	'digit' => [-2, sub {
-#		if ($val[1] *= 10) {
-#			$val[0] += $_/$val[1];
-#		} # fraction
-#		else {
-#			$val[0] = $val[0]*10+$_;
-#		} # integer
-#	}],
-	'digit'=> [-2, sub { $val[0] = ($val[1] *= 10) ? $val[0]+$_/$val[1] : $val[0]*10+$_ }],
-	'.'    => [-2, sub { $val[1] = 1 }], # decimal point
-	'eex'  => [-2, sub {}], # exponent
-	'chs'  => [1, sub {$val[0] = -$val[0]}], # negative
-
-	'<-'   => [-1, sub {
-		$val[0] = ($val[1] = int $val[1]/10)
-			? int($val[0]*$val[1])/$val[1] : int $val[0]/10
-	}], # backspace
-	'clx'  => [0, sub {@stack = (); @val = (0, 0); $nopush = 1}], # clear all
-
-	chr 13 => [0, sub {
-		unshift @stack, $val[0];
-		$nopush = 1;
+	'more' => [-1, sub {
+		$menumin += $set{menushow};
+		$menumin = 0 if $menumin>=$#menu;
+		showmenu();
+	}], # tab
+	'chs'  => [0, sub {$stack[0] = -$stack[0]}], # negative
+
+	'drop' => [0, sub {shift @stack}], # backspace
+	'clear'=> [0, sub {@stack = (); %val = (i=>undef, frac=>0) }], # clear all #todo: if (val{i}) delete char after cursor
+
+	'enter'=> [0, sub {
+		unshift @stack, defined $val{i} ? $val{i} : $stack[0];
+		%val = (i=>undef, frac=>0);
 	}], # duplication
 
-	'swap' => [1, sub {($val[0], $stack[0]) = ($stack[0], $val[0])}], # swap x<->y
-
-	'='    => [1, sub {$var{a} = $val[0]}], # copy
-	'>'    => [1, sub {$var{a} = $val[0]; $val[0] = shift @stack}], # assign
-
-	'+'    => [2, sub {$val[0] += shift @stack}], # addition
-	'-'    => [2, sub {$val[0] = shift(@stack) - $val[0]}], # substraction
-	'*'    => [2, sub {$val[0] *= shift @stack}], # multiplication
-	'/'    => [2, sub {$val[0] = shift(@stack) / $val[0]}], # division
-	'mod'  => [2, sub {$val[0] = shift(@stack) % $val[0]}], # modulo
-
-	'sqrt' => [1, sub {$val[0] = sqrt $val[0]}], # square root
-	'sq'   => [1, sub {$val[0] *= $val[0]}], # squared
-	'^'    => [2, sub {$val[0] = shift(@stack) ** $val[0]}], # exponentiation
-	'xroot'=> [2, sub {$val[0] = shift(@stack) ** (1/$val[0])}], # x-root of y
-
-	'log'  => [1, sub {$val[0] = log($val[0]) / log(10)}], # logarithm
-	'alog' => [1, sub {$val[0] = 10 ** $val[0]}], # 10^x
-	'ln'   => [1, sub {$val[0] = log $val[0]}], # natural logaritm
-	'lnp1' => [1, sub {$val[0] = log($val[0]+1)}], # ln(x+1)
-	'exp'  => [1, sub {$val[0] = exp($val[0])}], # e^x
-	'expm' => [1, sub {$val[0] = exp($val[0])-1}], # exp(x)-1
-
-	'sin'  => [1, sub {$val[0] = sin $val[0]}], # sine
-	'asin' => [1, sub {$val[0] = atan2($val[0], sqrt(1 - $val[0]*$val[0]))}], # inverse sine
-	'cos'  => [1, sub {$val[0] = cos $val[0]}], # cosine
-	'acos' => [1, sub {$val[0] = atan2(sqrt(1 - $val[0]*$val[0]), $val[0])}], # inverse cosine
-	'tan'  => [1, sub {$val[0] = sin($val[0]) / cos($val[0])}], # tangent
+	'swap' => [1, sub {@stack[0, 1] = @stack[1, 0]}], # swap x<->y
+
+	'='    => [1, sub {$var{a} = $stack[0]}], # copy
+	'?'    => [1, sub {$var{a} = shift @stack}], # assign
+
+	'+'    => [2, sub {$stack[1] += shift @stack}], # addition
+	'-'    => [2, sub {$stack[1] -= shift @stack}], # substraction
+	'*'    => [2, sub {$stack[1] *= shift @stack}], # multiplication
+	'/'    => [2, sub {$stack[1] /= shift @stack}], # division
+	'mod'  => [2, sub {$stack[1] %= shift @stack}], # modulo
+
+	'inv'  => [1, sub {$stack[0] = 1 / $stack[0]}], # 1/x
+	'sqrt' => [1, sub {$stack[0] = sqrt $stack[0]}], # square root
+	'sq'   => [1, sub {$stack[0] *= $stack[0]}], # squared
+	'^'    => [2, sub {$stack[1] **= shift @stack}], # exponentiation
+	'xroot'=> [2, sub {$stack[1] **= 1 / shift @stack}], # x-root of y
+
+	'log'  => [1, sub {$stack[0] = log($stack[0]) / log(10)}], # logarithm
+	'alog' => [1, sub {$stack[0] = 10 ** $stack[0]}], # 10^x
+	'ln'   => [1, sub {$stack[0] = log $stack[0]}], # natural logaritm
+	'lnp1' => [1, sub {$stack[0] = log($stack[0]+1)}], # ln(x+1)
+	'exp'  => [1, sub {$stack[0] = exp($stack[0])}], # e^x
+	'expm' => [1, sub {$stack[0] = exp($stack[0])-1}], # exp(x)-1
+
+	'sin'  => [1, sub {$stack[0] = sin $stack[0]}], # sine
+	'asin' => [1, sub {$stack[0] = atan2($stack[0], sqrt(1 - $stack[0]*$stack[0]))}], # inverse sine
+	'cos'  => [1, sub {$stack[0] = cos $stack[0]}], # cosine
+	'acos' => [1, sub {$stack[0] = atan2(sqrt(1 - $stack[0]*$stack[0]), $stack[0])}], # inverse cosine
+	'tan'  => [1, sub {$stack[0] = sin($stack[0]) / cos($stack[0])}], # tangent
 #	'atan' => [1, sub {}], # arctangent
 
-	'%'    => [2, sub {$val[0] /= shift(@stack)}], # percentage
-	'%ch'  => [2, sub {$val[0] = 100*(shift(@stack)-$val[0])/$val[0]}], # percentage change
-	'%t'   => [2, sub {$val[0] = 100*$val[0]/shift(@stack)}], # percentage total
-
-	'and'  => [2, sub {$val[0] = shift(@stack) & $val[0]}], # bitwise and
-	'or'   => [2, sub {$val[0] = shift(@stack) | $val[0]}], # bitwise or
-	'xor'  => [2, sub {$val[0] = shift(@stack) ^ $val[0]}], # bitwise xor
-	'not'  => [2, sub {$val[0] = ~$val[0]}], # bitwise not
-
-	'abs'  => [1, sub {$val[0] = abs $val[0]}], # absolute #todo
-	'sign' => [1, sub {$val[0] = $val[0] <=> 0}], # sign
-	'ip'   => [1, sub {$val[0] = int $val[0]}], # integer part
-	'fp'   => [1, sub {$val[0] -= int $val[0]}], # fractional part
-
-	'rnd'  => [1, sub {local $_ = 10**shift @stack; $val[0] = int(($val[0]+.5)*$_)/$_}], # round
-	'trnc' => [1, sub {local $_ = 10**shift @stack; $val[0] = int($val[0]*$_)/$_}], # truncate
-	'floor'=> [1, sub {$val[0] = int $val[0]}], # floor
-	'ceil' => [1, sub {$val[0] = int $val[0]+.9999}], # ceil
-
-	'min'  => [2, sub {
-		local $_ = shift @stack;
-		$val[0] = $_ if $_<$val[0];
-	}], # minimum
-	'max'  => [2, sub {
-		local $_ = shift @stack;
-		$val[0] = $_ if $_>$val[0];
-	}], # maximum
+	'sinh' => [1, sub {$stack[0] = ( exp($stack[0]) - exp(-$stack[0]) )/2}], # hyperbolic sine
+	'cosh' => [1, sub {$stack[0] = ( exp($stack[0]) + exp(-$stack[0]) )/2}], # hyperbolic cosine
+	'tanh' => [1, sub {$stack[0] = ( exp($stack[0]) - exp(-$stack[0]) )/( exp($stack[0]) + exp(-$stack[0]) )}], # hyperbolic tangent (sinh/cosh)
+	'asinh'=> [1, sub {$stack[0] = log( sqrt($stack[0]**2+1)+$stack[0] )}], # inverse hyperbolic sine
+	'acosh'=> [1, sub {$stack[0] = log( sqrt($stack[0]**2-1)+$stack[0] )}], # inverse hyperbolic cosine
+	'atanh'=> [1, sub {$stack[0] = log( (1+$stack[0]) / (1-$stack[0]) )/2}], # inverse hyperbolic tangent
+
+	'%'    => [2, sub {$stack[0] /= shift @stack}], # percentage
+	'%ch'  => [2, sub {$val{i} = 100*(shift(@stack)-$val{i})/$val{i}}], # percentage change
+	'%t'   => [2, sub {$val{i} = 100*$val{i}/shift(@stack)}], # percentage total
+
+	'and'  => [2, sub {$stack[1] &= shift @stack}], # bitwise and
+	'or'   => [2, sub {$stack[1] |= shift @stack}], # bitwise or
+	'xor'  => [2, sub {$stack[1] ^= shift @stack}], # bitwise xor
+	'not'  => [2, sub {$stack[0] = ~$stack[0]}], # bitwise not
+	'sl'   => [1, sub {$stack[0] *= 2}], # shift left
+	'sr'   => [1, sub {$stack[0] /= 2}], # shift right
+
+	'abs'  => [1, sub {$stack[0] = abs $stack[0]}], # absolute #todo
+	'sign' => [1, sub {$stack[0] = $stack[0] <=> 0}], # sign
+	'ip'   => [1, sub {$stack[0] = int $stack[0]}], # integer part
+	'fp'   => [1, sub {$stack[0] -= int $stack[0]}], # fractional part
+
+	'rnd'  => [1, sub {local $_ = 10**shift @stack; $val{i} = int(($val{i}+.5)*$_)/$_}], # round
+	'trnc' => [1, sub {local $_ = 10**shift @stack; $val{i} = int($val{i}*$_)/$_}], # truncate
+	'floor'=> [1, sub {$stack[0] = int $stack[0]}], # floor
+	'ceil' => [1, sub {$stack[0] = int $stack[0]+.9999}], # ceil
+
+	'min'  => [2, sub {local $_ = shift @stack; $stack[0] = $_ if $_<$stack[0] }], # minimum
+	'max'  => [2, sub {local $_ = shift @stack; $stack[0] = $_ if $_>$stack[0] }], # maximum
 
 	'dec'  => [0, sub {$set{base} = 10}], # decimal
 	'bin'  => [0, sub {$set{base} = 2}], # binary
 	'oct'  => [0, sub {$set{base} = 8}], # octal
 	'hex'  => [0, sub {$set{base} = 16}], # hexadecimal
-	'base36' => [0, sub {$set{base} = 36}], # alphanumerical
+	'base' => [1, sub {$set{base} = shift @stack}], # alphanumerical
+
+	'!'    => [1, sub {local $_ = $stack[0]; $stack[0] *= $_ while --$_>1}], # factor
+	'rand' => [0, sub {unshift @stack, rand}], # random value <1
+
+	'undo' => [0, sub {@stack = @{ $var{undo} }}], # undo
 ); # %action
 
+my %unit;
+{
+my $i = 0;
+$unit{$_->[0]} = { name=>$_->[0], type=>$i, val=>$_->[1] } for map {$i++; @$_} (
+	[
+		['m', 1],
+		['cm', .01],
+		['mm', .001],
+		['km', 1000],
+		['ft', .3048],
+		['in', .0254],
+		['yd', .9144],
+		['mile', 1609.344],
+		['nmile', 1852],
+		['lyr', 9.46052840488e+15],
+		['mil', 2.54e-5],
+	#		_m _cm _mm _yd _ft _in _Mpc _pc _lyr _au _km _mi
+	#		_nmi _miUS _chain _rd _fath _ftUS _Mil _μ _Å _fermi
+	], # lengths
+	[
+		['m^3', 1],
+		['cm^3', 1e-6],
+		['ft^3', .028316846592],
+		['in^3', 1.6387064e-5],
+	], # volume
+);
+} # create unit table
+
+
+sub error($) {
+	attron(A_REVERSE);
+	addstr(0, 0, shift);
+	attroff(A_REVERSE);
+	clrtoeol;
+	refresh;
+
+	ReadKey; # wait for confirm
+	1 while defined (ReadKey -1); # clear key buffer
+} # error
 
 sub showval($$);
 sub showval($$) {
 	my ($val, $base) = @_;
+	return '' unless defined $val;
 	return $val if $base==10;
 
 	my $int = int $val;
@@ -259,9 +309,10 @@ sub showstack() {
 
 sub showmenu() {
 	clrtoeol($height+2, 1);
-	for (grep exists $menu[$_], 1..$set{menushow}) {
+	my $nr = 0;
+	for (grep exists $menu[$_], $menumin+1..$menumin+$set{menushow}) {
 		my $sub = (my $s = $menu[$_]) =~ s/>\d+$//;
-		addstr($height+2, $width/$set{menushow}*($_-1), $_);
+		addstr($height+2, $width/$set{menushow}*($nr++), $_);
 		attron(A_REVERSE);
 		addstr($s);
 		attroff(A_REVERSE);
@@ -274,10 +325,12 @@ DRAW:
 clear;
 showmenu();
 showstack();
-addstr($height+1, 0, "> ");
+addstr($height+1, 0, "> ");  # prompt
 
 while (1) {
-	addstr($height+1, 2, showval($val[0], $set{base}));
+	addstr($height+1, 2, showval($val{i}, $set{base}));
+	addstr('_'.$val{unit}{name}) if exists $val{unit};
+	addstr($val{bla}) if exists $val{bla};
 	clrtoeol;
 	refresh;
 
@@ -286,48 +339,96 @@ while (1) {
 		while (defined (my $key = ReadKey -1)) {
 			$_ .= $key;
 		} # read additional keys
-	} # escape
-
-	exists $alias{$_}  and $_ = $alias{$_};
-	exists $falias{$_} and $_ = $menu[$falias{$_}];
-
-	if (exists $action{$_} or /^\d$/) {
-		my ($type, $cmd) = @{ $action{$_} || $action{digit} };
-		if ($type==-2) {
-			unshift @stack, $val[0] and showstack() unless $nopush;
-			@val = (0, 0) if $nopush<2; # replace current
-			$nopush = 2;
-		} # modify value
-		$cmd->();
-		$nopush = 0 if $type>0;
-		showstack() if $type>=0;
-	} # some operation
+	} # escape sequence
+
+	exists $alias{$_}  and $_ = $alias{$_};  # command shortkeys
+	if (exists $falias{$_}) {
+		unless ($_ = $menu[$falias{$_}]) {
+			error("* no such menu entry *");
+			goto DRAW;
+		}
+	} # function key
+
+	$_ = delete $val{bla} if exists $val{bla} and $_ eq 'enter';
 
-	elsif ($_ eq 'quit') {
+	if ($_ eq 'quit') {
 		last;
 	} # quit
 	elsif ($_ eq 'refresh') {
 		goto DRAW;
 	} # refresh
 
+	elsif (exists $val{bla} or /^[A-Z]$/) {
+		if (defined $val{i}) {
+			unshift @stack, $val{i};
+			%val = (i=>undef, frac=>0);
+			showstack();
+		} # enter present value
+		if ($_ eq "drop") {
+			$val{bla} = substr $val{bla}, 0, -1 or delete $val{bla};
+		} # backspace
+		else {
+			$val{bla} .= lc $_;
+		} # add character
+	} # manual command
+
+	elsif (/^\d$/) {
+		$val{i} = 0 unless defined $val{i};
+		$val{i} = ($val{frac} *= 10) ? $val{i}+$_/$val{frac} : $val{i}*10+$_;
+	}
+	elsif ($_ eq '.') {
+		$val{i} = 0 unless defined $val{i};
+		$val{frac} = 1;
+	} # decimal point
+	elsif ($_ eq 'eex') {
+		$val{i} = 1 unless defined $val{i};
+		#todo
+	} # exponent
+	elsif ($_ eq 'chs' and defined $val{i}) {
+		$val{i} = -$val{i};
+	} # change sign
+	elsif ($_ eq 'drop' and defined $val{i}) {
+		$val{i} = ($val{frac} = int $val{frac}/10)
+			? int($val{i}*$val{frac})/$val{frac} : int $val{i}/10
+	} # backspace
+
+	elsif (exists $action{$_} or /^\d$/) {
+		my ($type, $cmd) = @{ $action{$_} };
+		if ($type>0 and defined $val{i}) {
+			unshift @stack, $val{i};
+			%val = (i=>undef, frac=>0);
+		} # auto enter
+		if ($type>0 and $type>@stack) {
+			error("* insufficient stack arguments for operation *");
+			goto DRAW;
+		} # insufficient arguments
+		$var{undo} = [@stack] if $type>=0 and $_ ne 'undo';
+		$cmd->();
+		showstack() if $type>=0;
+	} # some operation
+
 	elsif (/>(\d+)$/) {
 		@menu = @{ $menus[$1] };
+		$menumin = 0;
 		showmenu();
 	} # submenu
 
-	else {
-		attron(A_REVERSE);
-		addstr($height+1, 0, "* error: ".join(' ', map ord, split //, $_)." *");
-		attroff(A_REVERSE);
-		clrtoeol;
-		refresh;
+	elsif ($_ =~ /^_/) {{
+		$_ = $unit{substr $_, 1} or next;
+		if (exists $val{unit} and $val{unit}{type}==$_->{type}) {
+			unshift @stack, $val{i} if defined $val{i};
+			$stack[0] *= delete($val{unit})->{val} / $_->{val};
+			showstack();
+			%val = (i=>undef, frac=>0);
+		} # convert
+		else {
+			$val{unit} = $_;
+		} # set source unit
+	}} # conversion
 
-		ReadKey; # wait for confirm
-		1 while defined (ReadKey -1); # clear key buffer
+	else {
+		error("* error: ".join(' ', map ord, split //, $_)." *");
 		goto DRAW; # screen messed up
-	}
+	} # error
 } # input loop
 
-ReadMode 0;
-endwin;
-