Prob macro while following Guide documentation throws "AssertionError: model isa Model"

[sketchballshane]

While following the Guide tutorials (https://turing.ml/dev/docs/using-turing/guide) we came across an assertion error.

@model function gdemo(x, y)
    s ~ InverseGamma(2, 3)
    m ~ Normal(0, sqrt(s))
    x ~ Normal(m, sqrt(s))
    y ~ Normal(m, sqrt(s))
end

prob"x = 1.0, y = 1.0 | model = gdemo, s = 1.0, m = 1.0"

ERROR:
AssertionError: model isa Model

Julia: 1.5.2
Turing: 0.14.10

[devmotion]

Unfortunately, the tutorials are outdated (see TuringLang/docs#86). It should work if you use the model instance instead of gdemo, i.e., model = model if you had a model model = gdemo(...).

[yebai]

Closed in favour of #356