Cheat Sheet for Experienced Programmers
TMBASIC is a statically- and nominally-typed BASIC language.
Roughly speaking, it is a cross between QBASIC and Visual Basic (pre-.NET).
┌─ Supported features ─────────────────────────────────────────────────┐
│ √ Statically typed (vs. dynamic) √ if, for, for each, while │
│ √ Nominal type system (vs. structural) √ print, input │
│ √ Exception-based error handling │
└──────────────────────────────────────────────────────────────────────┘┌─ Unsupported QBASIC features ─┐ ┌─ Unsupported VB features ────────┐
│ No line numbers │ │ No object oriented programming │
│ No "goto" │ │ No multithreading │
│ No "peek" or "poke" │ │ No graphics or sound support │
│ No type suffixes, like $ │ │ No interop with C/C++ │
└───────────────────────────────┘ └──────────────────────────────────┘
Data types
- Boolean — true / false.
- Number — 128-bit decimal floating point.
- String — UTF-8 text.
- Date — Date without a time.
- DateTime — Date and time, without a time zone.
- DateTimeOffset — Date, time, and fixed time zone offset from UTC.
- TimeZone — Offset from UTC and daylight saving time schedule.
- TimeSpan — Period of time.
- List of T — Generic dynamic-sized array with element type T. Example: List of Number. Literals look like: [0, 1, 2].
- Map from K to V — Generic dynamic-sized dictionary with key type K and value type V. Example: Map from Number to String.
- Set of T — Generic dynamic-sized set containing unique elements of type T. Example: Set of Number.
- Optional T — Wrapper for type T indicating that the value may or may not be present. Example: Optional Number.
- Record (...) — Anonymous record type, containing zero or more named fields. Example: Record (foo as Number, bar as String). Literals look like {foo: 1, bar: "hi"}.
- Named record types. These are defined using type ... end type blocks.
There are no object or reference semantics in TMBASIC, and thus no real support for object oriented programming (OOP).
Everything is a value.
Assigning to a variable always makes a copy, even for records, lists, and maps.
Procedure parameters are passed by value.
Internally, TMBASIC uses immutable data structures to make this efficient.
Sample code
if statements
sub FizzBuzz(n as Number)
dim fizz = (n mod 3) = 0
dim buzz = (n mod 5) = 0
if fizz and buzz then
print "FizzBuzz"
else if fizz then
print "Fizz"
else if buzz then
print "Buzz"
else
print n
end if
end function
sub Main()
dim n as Number
print "Enter a number, or 0 to quit: ";
input n
if n <> 0 then FizzBuzz n
end sub
Build a list efficiently with dim list
function Fibonacci(count as Number) as List of Number
dim a = 0
dim b = 1
dim list numbers
yield a
yield b
for i = 3 to count
dim c = a + b
yield c
a = b
b = c
next
end dim
return numbers
end function
sub Main()
for each n in Fibonacci(50)
print n
next
end sub