> A variable in algebra is exactly what you consider a constant in a programming language. I disagree. A constant is not expected to change, a variable is abso

> A variable in algebra is exactly what you consider a constant in a programming language. I disagree. A constant is not expected to change, a variable is absolutely expected to change. The difference is that a mathematical variable changes "between invocations" of a mathematical statement. An "assignable" changes "within invocations".