Variable Types

Variables in Retro Rocket BASIC must follow these rules:

1. Variables must start with an alphabetic character or an underscore, e.g. A–Z, a–z or _.
2. Variables may contain numeric characters, but not as the first character.
3. After the first character, a variable may contain any alphanumeric or underscore character in any position.
4. Variable names have a maximum length of 60 characters (excluding array subscripts). This is to encourage readability.
5. Variable names may be suffixed with:
   • $ → string variable
   • # → real (floating-point) variable These suffixes are not permitted elsewhere in the name.
6. Variable names are CaSe SeNsItIvE.
7. Variable names cannot start with a keyword or built-in function name.

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Regular expression

The following pattern matches valid Retro Rocket BASIC variable names:

/[A-Za-z_][A-Za-z_0-9]{1,58}(\$|#|[A-Za-z_0-9])/

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Types of Variables

• Integer Variables
• Real Variables
• String Variables
• Array Variables
• Built-In Variables