Add variables in a container

[odow]

You don’t have to use JuMP types as containers. See:

using JuMP
model = Model()
n = 10
x = Dict(
    i => @variable(model, base_name = "x_$(i)")
    for i = 0:n
)

n += 1
x[n] = @variable(model, base_name = "x_$I")
@constraint(model, x[n] <= foo(n))