BASIC Language Reference

Creating BASIC programs

Programs in Retro Rocket BASIC are similar in structure to other BASIC dialects, with some important differences:

• Line numbers are optional.
  • If used, each must be greater than the one before it.
  • Gaps in numbering are allowed.
  • If the first character of the file is not a digit (0–9), the program is assumed to have no line numbers.
• Sequential execution. Programs execute line by line, top to bottom, unless redirected with control statements (e.g. GOTO, IF, PROC, FUNCTION).
• Statements. Each line must contain at least one valid statement, with any required parameters.
• Variables. Four types of variables are available (see Variable Types). Variables may be:
  • Local to the current program, or
  • Inherited by other programs run with CHAIN or similar mechanisms.

For real-world examples of programs in the operating system, see the os/programs directory in the source tree.

---

Further Reference

• Beginners' Tutorial
• Variable Types
• Keywords
• Built-In Functions
• Audio Introduction
• BASIC Networking
• Libraries
• Writing BASIC Tasks
• BASIC Inerpreter Development Guide