The Kyma Language for Sound Design, Version 4.5

Variables
By introducing variables, we can generalize one particular Sound to describe a whole class of Sounds.
Such an abstracted Sound is called a lifted Sound, so-called because it is at a “higher” level of abstraction
than is any specific Sound.
A single lifted Sound represents an infinite number of real Sounds. Lifting a Sound by introducing variables
is similar to introducing variables into an arithmetic expression. While 4 + 5 is just one expression,
x + y represents a whole class of expressions — all possible sums of two numbers.
There are two places you might want to use variables: when encapsulating a complex Sound (see The
Class Editor on page 536), or in a Script or in one of the various FileInterpreters (see Scripting on page
522).
Kyma Variables
Variables
Variable Sounds
In Kyma there are three kinds of variables: variables, Variable Sounds, and SoundCollectionVariables. A
variable is used to represent values you can type into parameter fields, a Variable Sound acts as a place
holder for Sounds, and a SoundCollectionVariable represents a collection of Sounds.
The typeable parameters of a Sound can be represented by variables or expressions involving variables.
To assign a variable to a parameter, type a name for the variable preceded by a question mark:
The variable will be displayed in green in the parameter field.
A Variable functions as a place holder for an actual Sound that may be assigned to it later on. You can use
a Variable anywhere you would use any other Sound.
SoundCollectionVariables
Sometimes you may want to set an entire collection of Sounds (rather than the individual Sounds of a
collection) to a variable — for example, in the Inputs field of a Concatenation or a Sum. To do this, drag
SoundCollectionVariable from the system prototypes into the Inputs parameter field. The SoundCollectionVariable
acts as a place holder for a collection of Sounds. It can be placed only in fields that accept
more than one Sound.
You can use SoundCollectionVariables in defining a new kind of Sound that can take multiple inputs (see
The Class Editor on page 536 for more information). You can also use a Script to set the value of a
SoundCollectionVariable. Its value should be a collection of Sounds (for example, an Array). See
Scripting on page 522 and The Smalltalk-80 Language on page 513 for more information.