coffee_class.coffee

# 只會被執行一次, 而不是每次new 都執行
myvar_init = ->
  console.log 'got myvar_init'
  3


# class 不是典型的declare , class內所有的member 都佔有實體, class member 真正在做的是設定初始值, 而非type
class Packet
  debugFlags : false
  stpMac: new Buffer [ 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 ]
  stpPdu:
    llc: new Buffer [0x42, 0x42, 0x03]
  myvar: (myvar_init()+15; -50)
  dosome: ->
    @stpMac[0]+=1
  qq: 99

#這樣總共有三份 pkt1, pkt2, Packet
pkt1 = new Packet
console.log 'Packet::myvar = ', Packet::myvar
console.log 'pkt1.myvar = ', pkt1.myvar

pkt1.myvar=4
Packet::myvar=8
pkt2 = new Packet
console.log 'Packet::myvar = ', Packet::myvar
console.log 'pkt1.myvar = ', pkt1.myvar
console.log 'pkt2.myvar = ', pkt2.myvar

pkt1.debugFlags = true
pkt2.debugFlags = false
console.log 'pkt1 debug flags =', pkt1.debugFlags
console.log 'pkt2 debug flags =', pkt2.debugFlags

#buffer 只是傳 reference, 所以三個一起共享 stpMac
console.log 'pkt1.stpPdu = ', pkt1.stpPdu
pkt1.stpMac[0]=0x99
console.log 'pkt1.stpMac = ', pkt1.stpMac
console.log 'pkt2.stpMac = ', pkt2.stpMac

pkt1.dosome()
console.log 'pkt1.stpMac = ', pkt1.stpMac
pkt1.dosome()
console.log 'pkt2.stpMac = ', pkt2.stpMac



# 用class 去new 兩個便