How to evaluate a shell variable each time it's used

Question

Related to a similar problem I\'m having: zsh not re-computing my shell prompt

Is there any way to define a shell variable such that its value is calculated each tim

Answer 1

That's not possible. Use a function instead:

my_date() {
    echo "today is $(date)"
}

# use it
echo "$(my_date)"

Note: This is bash syntax; your shell might use a slightly different syntax.