Editing BASIC Programming (section)

===Language features===

VCS BASIC supports the following keywords:<ref>{{cite book|title=BASIC Programming: Atari Game Program Instructions|date=1979|publisher=Atari, Inc.|location=Sunnyvale, CA}}</ref>
* Statements: <code>Print</code>
* Structure: <code>Goto</code>, <code>If-Then-Else</code>
* Graphics: <code>Clear</code>
* Functions: <code>Hit</code>, <code>Key</code>
* Math: <code>+ - × ÷ Mod</code>
* Relational operators: <code>< > =</code>

Unlike most BASIC implementations of the time:
* VCS BASIC uses ← instead of = for assignment; e.g., <code>A←A+1</code>.
* Statements can be strung together on a line without a delimiter; e.g., <code>Note←APrintA</code>.
* An <code>If</code> statement can be used as a function, returning a value: <code>{{codett|2=cbmbas|Ver1←Ver1+IfVer1}}[[Modulo operation|Mod]]2{{codett|2=cbmbas|Then8}}{{codett|2=monkey|Else}}92</code>
* <code>If</code> statements can take an <code>Else</code> clause.

Special variable names:
* <code>Note</code> sounds a musical note, assigned numbers from 0 to 7
** Numbers assigned to <code>Note</code> are implicitly assigned modulus 8, thus 8 becomes 0, 9 becomes 1, etc.
* <code>Hor1</code>, <code>Hor2</code> - the horizontal coordinate of one of two squares
* <code>Ver1</code>, <code>Ver2</code> - the vertical coordinate of one of two squares

The language supports 26 unsigned integer variables A to Z. VCS BASIC supports integers from 0 to 99. Math operations wrap, so 99+1 becomes 0, 99+2 becomes 1, etc.

====Sample code====
The following example of a ''[[Pong]]'' game is provided.
{{pre|
1 Hor2←2+Key
2 {{codett|2=cbmbas|IfVer1>90ThenVer1←88}}
3 {{codett|2=cbmbas|IfHit}}{{codett|2=cbmbas|ThenVer1←9}}
4 {{codett|2=cbmbas|Ver1←Ver1+IfVer1}}[[Modulo operation|Mod]]2{{codett|2=cbmbas|Then8}}{{codett|2=monkey|Else}}92
5 Hor1←Hor1+7
6 {{codett|2=cbmbas|Goto1}}
}}