Outlines how binary flags work.

scriptie-talkie-flags.md

Scriptie Talkie Log

In case this doesn't work in your browser.

Outlines how binary flags work.

Script

var alive = parseInt('0001', 2);
var kicking = parseInt('0010', 2);
var alive_kicking = parseInt('0011', 2);
var dead = parseInt('0100', 2);

// removing a flag
alive_kicking & ~alive;   // kicking
alive_kicking & ~kicking; // alive

// adding flag
alive | kicking;  // alive and kicking

// adding already existing flag
alive_kicking | alive; // still alive and kickin

// checking 'has flag'

// alive and kicking has alive?
alive_kicking & alive;

// alive kicking has dead?
alive_kicking & dead;

Scriptie Talkie Output

1: var alive = parseInt('0001', 2);
+  alive: 1
 
 2: var kicking = parseInt('0010', 2);
+  kicking: 2
 
 3: var alive_kicking = parseInt('0011', 2);
+  alive_kicking: 3
 
 4: var dead = parseInt('0100', 2);
+  dead: 4
 
 5: 
 6: // removing a flag
 7: alive_kicking & ~alive;   // kicking
=> 2
 
 8: alive_kicking & ~kicking; // alive
=> 1
 
 9: 
10: // adding flag
11: alive | kicking;  // alive and kicking
=> 3
 
12: 
13: // adding already existing flag
14: alive_kicking | alive; // still alive and kickin
=> 3
 
15: 
16: // checking 'has flag'
17: 
18: // alive and kicking has alive?
19: alive_kicking & alive;
=> 1
 
20: 
21: // alive kicking has dead?
22: alive_kicking & dead;
=> 0