model{
    prec.ybar <- n/sigma2
    prec.theta <- 1/tau2
    ybar  ~ dnorm(theta, prec.ybar)
    theta ~ dnorm(mu, prec.theta)
    }
    
DATA:
list(ybar=6, mu=2, sigma2=1, tau2=1, n=1)

INITS:
list(theta = 0)