2.8) More On The Equal Sign

As an example of a statement that makes sense in programming but is nonsense in math, consider.

A=10.0
A=A+1.0

In programming, when the computer comes to this bit of the program it will first use the value of 10.0 to assign it to A. On the next line it works out the RHS first so that A=10.0 is added to 1.0 to become 11.0 and it will be assigned to the LHS variable A. So now A=11.0.
In mathematics, the second equation isn’t satisfied by A=10. This is why you must view the = sign as an assignment operator.
Finally, on the LHS you must only have a single variable (not a number and not a formula). A+1.0=A makes no sense in programming since the value on the right cannot be assigned to the LHS since it is a calculation on the LHS. Likewise, 10=A makes no sense in programming because the RHS cannot be assigned to the LHS.