Concatene string with dynamic data in jade node js

Anyone knows how to concatene a string with a dynamic data for passe it into a form template?

My controller is :

exports.edit = function(req, res) {
    var id = req.params.id;
    Product.findOne({id: id}, function(err, doc){
        if (err) {
            res.send("There is no product with this " + id + "!")
        } else {
            res.partial('products/edit', {title: "Edit", product: doc});
        }
    });
};

my products/edit.jade file is :

-if (product != null)
    h2 Edit
    form.form-edit(method="post", action="products/#{product.id}", name="form-edit")
        !=partial("inc/form-edit", { type: "Edit", image: "../img/" + #{product.image}})
                                                  // Doesn't work, i can pass only strings to my form template

and my inc/form-edit.jade file is:

.....
    input#bt-prod-edit.btn.btn-primary(type="button", value="Parcourir")
    img(src="#{image}")
    div.align-center
      input.bt-cancel.btn(type="button", name="bt-cancel", value="Annuler")
      input#bt-prod-edit.btn.btn-primary(type="submit", name="bt-prod-edit", value="#{type}")

So if I do

!=partial("inc/form-edit", { type: "Edit", image: "image_path"})

works fine but if I try to passe any dynamic data I have an error message : Unexpected token ILLEGAL

Does anyone know why?

Thank you very much