This class provides the basic mechanism to do String Interpolation.
String Interpolation allows users
to embed variable references directly in *processed* string literals.
Here's an example:
Appends all elements of this collection to a string builder using start, end, and separator strings.
The written text begins with the string start and ends with the string end.
Inside, the string representations (w.r.t. the method toString)
of all elements of this collection are separated by the string sep.
Appends all elements of this collection to a string builder using a separator string.
The written text consists of the string representations (w.r.t. the method toString)
of all elements of this collection, separated by the string sep.
Appends all elements of this collection to a string builder.
The written text consists of the string representations (w.r.t. the method
toString) of all elements of this collection without any separator string.