Tibbo GA1000, User Manual

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61 TIDE and Tibbo BASIC User Manual
©2000-2008 Tibbo Technology Inc.
const universal_answer = 42
const copyright = "(c) 2005 Widget Systems Inc." ' this is a string
constant
const escape_char = `@` ' this constant will contain a numerical value --
the ASCII code for the char @.
const hexi = &hFB ' would create a constant with a value of 251 (&hFB in
hex)
const bini = &b00110101 ' would create a constant with a value of 53
(&b00110101 in binary)
const width = 10
const height = 15
const area = width * height ' constants may contain expressions which
include other constants
dim x as byte
const foo = x + 10 ' this will produce a compiler error. Constant
expressions may contain only constants.
Constants can be useful when you have some values which are used throughout
the code; with constants, you can define them just once and then refer to them by
their meaningful name. This has the added benefit of allowing you to easily change
the value for the constant any time during the development process -- you will just
have to change the definition of the constant, which is a single line of code.
When defining a list of related constants, it is often convenient to use
the
Enum Statement and create one data type which contains this
list of constants. See also User-Defined Types above.
When defining a constant within a scope , this constant is visible only from
within this scope. It is a good idea to define all constants within header files, and
include these files into each compilation unit.
String constants
String constants can include escape sequences to define unprintable characters.
This functionality is borrowed from C. Adding unprintable characters to the string
has always been rather inconvenient in BASIC language. The only way to do so
was like this:
s = "abc"+chr(10)+chr(13) 'add LF/CR in the end
In Tibbo Basic you can achieve the same by using escape sequences -- C style:
s = "abc\n\f" ''\n' means LF, '\f' -- CR
const STR1 = "abc\x10\x13" 'same result can be achieved using HEX codes of
the characters
The following standard escape sequences are recognized:

"\0" for ASCII code 0

"\a" for ASCII code 7 (&h7)

"\b" for ASCII code 8 (&h8, BS character)
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