I wanted to make something distinctly perl, and despite its many powers, perl is best known for its unmatched text manipulation capabilities. Therefore, I endevored to write a binary clock program based upon string matching. It operates as a finite state machine, where the current state is the binary string representing each digit. No arithmatic takes place.

I was able to construct the core of the clock in one horrendously (beautiful?) long line of code,with a couple of extra lines for initilization and printing.

The current time can be set using command line aurguments like:

perl 438277.pl 0000 0011 0001 0111

The example above sets the current time to 3:17. The clock defaults to 1:00 if no command line aurguments are provided. 

use warnings;use strict;
(@ARGV eq 4)?(($",$~,$:,$.) = @ARGV,$^=$_='0000'):
($"=$_=$^=$.=$:='0000',$~='0001');{$|=1;select $,,$,,$,,1;
((s:0000:0001:)?():((s:0001:0010:)?():((s:0010:0011:)?():((s:0011:0100
+:)?():((s:0100:0101:)?():((s:0101:0110:)?():((s:0110:0111:)?():((s:01
+11:1000:)?():((s:1000:1001:))))))))))?():((s:1001:0000:)?((($^=~s:000
+0:0001:)?():(($^=~s:0001:0010:)?():(($^=~s:0010:0011:)?():(($^=~s:001
+1:0100:)?():(($^=~s:0100:0101:))))))?():(($^=~s:0101:0000:)?((($.=~s:
+0000:0001:)?():(($.=~s:0001:0010:)?():(($.=~s:0010:0011:)?():(($.=~s:
+0011:0100:)?():(($.=~s:0100:0101:)?():(($.=~s:0101:0110:)?():(($.=~s:
+0110:0111:)?():(($.=~s:0111:1000:)?():(($.=~s:1000:1001:))))))))))?()
+:(($.=~s:1001:0000:)?((($:=~s:0000:0001:)?():(($:=~s:0001:0010:)?():(
+($:=~s:0010:0011:)?():(($:=~s:0011:0100:)?():(($:=~s:0100:0101:))))))
+?():(($:=~s:0101:0000:)?((($~=~s:0000:0001:)?():(($~=~s:0001:0010:)?(
+):(($~=~s:0010:0011:)?(($"=='0001')?($~=$",$"='0000'):()):(($~=~s:001
+1:0100:)?():(($~=~s:0100:0101:)?():(($~=~s:0101:0110:)?():(($~=~s:011
+0:0111:)?():(($~=~s:0111:1000:)?():(($~=~s:1000:1001:))))))))))?():((
+$~=~s:1001:0000:)?(($"=~s:0000:0001:)?():($"=~s:0001:0000:)):())):())
+):())):())):()),
(print "\r",$",' ',$~,':',$:,' ',$.,':',$^,' ',$_)&&redo}

[download]
If you really want time to fly, change the '1' in the 'select $,,$,,$,,1;' statement to '0'.

UPDATE: Something went wrong when I posted the code the first time. I have replaced it with code that should work as advertized.

Replies are listed 'Best First'.
Re: Binary Clock Implemented Through String Matching
by belg4mit (Prior) on Mar 12, 2005 at 15:09 UTC
    It's more of a binary representation of a normal clock, seeing as you use a nybble per digit. Here's a cleaned up version (did you mean to post to obfuscated code instead?), I replaced the space in the output with a . because the eye was drawn to it too much. 
    use strict;use warnings;$|=1;
(@ARGV eq 4) ? ( ($",$~,$:,$.) = @ARGV,$^=$_='0000') : ($"=$_=$^=$.=$:
+='0000',$~='0001');
{
  select undef,undef,undef,1;0
  ||    s:0000:0001: ||    s:0001:0010:
  ||    s:0010:0011: ||    s:0011:0100:
  ||    s:0100:0101: ||    s:0101:0110:
  ||    s:0110:0111: ||    s:0111:1000:
  ||    s:1000:1001: ||    s:1001:0000:
  &&$^=~s:0000:0001: ||$^=~s:0001:0010:
  ||$^=~s:0010:0011: ||$^=~s:0011:0100:
  ||$^=~s:0100:0101: ||$^=~s:0101:0000:
  &&$.=~s:0000:0001: ||$.=~s:0001:0010:
  ||$.=~s:0010:0011: ||$.=~s:0011:0100:
  ||$.=~s:0100:0101: ||$.=~s:0101:0110:
  ||$.=~s:0110:0111: ||$.=~s:0111:1000:
  ||$.=~s:1000:1001: ||$.=~s:1001:0000:
  &&$:=~s:0000:0001: ||$:=~s:0001:0010:
  ||$:=~s:0010:0011: ||$:=~s:0011:0100:
  ||$:=~s:0100:0101: ||$:=~s:0101:0000:
  &&(
    $~=~s:0000:0001: ||$~=~s:0001:0010:
  ||(
    $~=~s:0010:0011: ? $"=='0001'
  &&(
    $~=$"            , $" ='0000'
  ):$~=~s:0011:0100: or$~=~s:0100:0101:
  or$~=~s:0101:0110: or$~=~s:0110:0111:
  or$~=~s:0111:1000: or$~=~s:1000:1001:
  )) 
  ||$~=~s:1001:0000: &&$"=~s:0000:0001:
  ||$"=~s:0001:0000:;
  print "\r", $",'.',$~,':',$:,'.',$.,':',$^,'.',$_;
  redo
}

    [download]
    Replace line 2 with this block to use the current time 
    @_=localtime;
$~=$_[2]%12%10;$"=$_[2]%10>9;
$.=$_[1]%10;$:=$_[1]-$.;$:/=10;
$_=$_[0]%10;$^=$_[0]-$_;$^/=10;
foreach $,($~,$",$.,$:,$_,$^){$, = sprintf"%04b",$,;}

    [download]

    --
    I'm not belgian but I play one on TV. On dit que je parle comme un belge aussi.

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[d/l]
[select]
Re: Binary Clock Implemented Through String Matching
by zentara (Cardinal) on Mar 11, 2005 at 12:17 UTC
    I'm not sure how this all works, but when I run it on linux, all I get is a repeating line: 
    0000 0001:0000 0000:0000 01

    [download]
    I'm not really a human, but I play one on earth. flash japh
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[d/l]
Re: Binary Clock Implemented Through String Matching
by Vynce (Friar) on Mar 16, 2005 at 09:23 UTC
    i'm very curious why you named the program what you did -- my first thought was that it was the number of seconds until it looped or something, but that seems obviously not the case. enlightenment?
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