Variables

[Kent Johnson]

Richard Blackwood wrote:
>>> To All:
>>>
>>>    Folks, I need your help. I have a friend who claims that if I write:
>>>
>>> foo = 5
>>>
>>> then foo is NOT a variable, necessarily. 
>>
> Indeed, this language is math. My friend says that foo is a constant and 
> necessarily not a variable. 

Well, we mostly talk Python here, not math. In Python, if you say
foo = 5
foo is a name bound to an immutable value.

If I had written foo = raw_input(), he would
> say that foo is a variable. 

That's funny. foo is still a name bound to an immutable (string) value. foo is no more or less 
variable than it was with foo = 5.

Which is perfectly fine except that he
> insists that since programming came from math, the concept of variable 
> is necessarily the identical. This can not be true. For example, I may 
> define foo as being a dictionary, but I can not do this within math 
> because there is no concept of dictionaries within mathematics; yet foo 
> is a variable, a name bound to a value which can change.

Sounds like you are having a stupid and meaningless argument with your friend. What you call foo 
won't change what it is. He should learn Python, then he would understand the true zen of foo.

Kent