[gnugo-devel] need help

[max-d]

;xterri(a) && !attack(B) && !attack(C) && !oplay_attack(*,?,a,a)
;&& !oplay_defend_both(*,?,a,B,C)

in this auto-helper constraint expression , i can't find any explanation
about the meaning of the "!" sign which often begins some functions

-what difference between !attack(B)  and attack(B) ?

-about the 2 lines of the expression
; expression A
; expression B
i suppose the pattern matcher accepts if  A and B are  true ..


-about  this function :
!oplay_attack(*,?,a,a)
O plays at * then X tenukis then O plays at "a"
the function returns true if O then does attack its own move "a"...

-same thing here
!oplay_defend_both(*,?,a,B,C) ..
BC being X stones

 i'm afraid i'm missing something !

-i believe  C uses  && for logical AND, || for logical OR.
But i'm not sure .
Is it right ?

thanks for your time !
md

the full pattern...

ED70
# Threaten to capture some stones.

O*X
OX.

:8,OXe,followup(6)

O*C
OBa

;xterri(a) && !attack(B) && !attack(C) && !oplay_attack(*,?,a,a)
;&& !oplay_defend_both(*,?,a,B,C)