Common Music Dictionary

Definition terms are printed in fixed-width bold face:

cents->scaler
Literals and programming code are printed in fixed-width face:
(list (note 60) (rhythm 'h.))
Variables and metavariables (names that stand for pieces of code) are printed in italic face:

number
Terms separated by | are exclusive choices where exactly one must apply:

number | boolean
Braces { } and brackets [ ] are sometimes used to associate or group the enclosed terms and are not part of actual code.
- Braces group the enclosed terms into a single entity. Thus:
  
  {number | boolean}
  
  describes single value that is either a number or a boolean.
- Brackets make the enclosed term optional. An optional term may appear at most one time. For example, in the following definition:
  
  (odds prob [trueval] [falseval])
  
  prob is a required argument that may be followed by up to two optional values. Thus, each of the following calls is correct:
```
(odds .5)
(odds 1 'win)
(odds .2 "Yup" "Nope")
```
A star * after a brace means that the enclosed terms may be specified zero or more times. For example:

(new class {keyword value}*)

means that any number of keyword and value pairs, including none, may follow the required class argument. Each of the following calls is correct:

(new midi) (new midi :time 10) (new midi :keynum 22 :duration 3)
A plus + after a brace means that the enclosed terms may be specified one or more times.
A sequence of three dots means the rest of the arguments, no matter how many. For example:

(pick arg ...)

means that any number of additional values, including none, may follow arg.
Evaluation is indicated using the right arrow:

⇒
Syntax highlighting distinguishes important syntactic units:

keyword string special comment

:music "Hello, world" loop ;; bug!