Item

An Item is a single number (numeric Item) or string (literal Item).

It is used to represent calculus elements like : -3 ; +4.5 ; 296 ; 10³⁺⁸ ; (-8)²
and like : 'A' ; 'CD' ; 'x' ; 'b²' ; '-y³'
but not elements like : -5x², which can be represented by a Product of two Items (-5 and 'x²') or by a Monomial.

An Item embeds a Value.

It is an Exponented and its exponent is an Exponented itself, so it allows more complicated objects like 4^(x^2)

Possible args for __init__() :

Fields :

Debugging info :