Special Operators

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Special Operators help to make math operations faster and are generally quicker to type out as well. There are currently 4 special operators supported in Second BASIC:

• Increment Operator (++)
• Decrement Operator (--)
• Self Referencing Addition (+=)
• Self Referencing Subtraction (-=)

Here are some common uses of each of the operators:

Increment Operator: The increment operator will increment a long or integer data type by 1. Instead of using a = a + 1, you can do a++

Using the method of a = a + 1, the compiler will generate the following assembly code:

clr.l d0      move.w (__INTEGER_a), d0      add.w #1, d0;      move.w d0, (__INTEGER_a)

Using the increment operator, the compiler generates the following assembly code:

addq.w #1, (__INTEGER_a)

Decrement Operator: The decrement operator functions exactly like the increment operator, except instead of adding 1, it subtracts 1.

Self Referencing Addition Operator: The self referencing operators will add or subtract the expression from the variable without having to reference it in the expression. For example, a = a + 3 * b would look like a+=3*b.

Using the first method, the assembly output is:

clr.l d0      move.w (__INTEGER_a), d0      add.w #3, d0;      mulu  (__INTEGER_b), d0      move.w d0, (__INTEGER_a)

The self referencing operator outputs the following assembly code:

move.l #3, d0      mulu  (__INTEGER_b), d0      add.w d0, (__INTEGER_a)

Self Referencing Subtraction Operator: The self referencing subtraction operator acts just like the self referencing addition operator, except it will subtract the expression instead of adding.