1. Introduction

Manual Notation

This manual uses a small number of typographic conventions:

Body text appears in Roman.

First uses of terms appear in Bold.

Text which appears as it would be entered into the computer appears in Courier.

In the body of the manual, the following notation is used to describe syntax forms:

{...}

Curly braces indicate a group of items.

{...}*

Curly braces followed by an asterisk indicate that the contents can appear zero or more times.

{...}+

Curly braces followed by a plus sign indicate that the contents can appear one or more times.

[...]

Square brackets indicate that the contents are optional.

...|...

Items separated by a vertical bar are mutually exclusive. One or the other may appear.

The BNF grammar at the end of the manual uses its own notation which is different from the above.

Formal parameters (i.e., place holders for the actual text you would enter) appear in Italic. The names of parameters are often descriptive of the type of value acceptable as a value of the parameter. They will often match the names of classes, indicating a general instance of the class. For example, number indicates a general instance of the class <number>, and string indicates a general instance of the class <string>.

Interactions between a user and a Dylan interpreter are shown in a mixture of Courier and Courier Italic. Courier shows the text entered by the user, and Courier Italic shows the text printed by the interpreter. The question mark used in these sections is the interpreter's prompt.[3]

The error messages in the manual have been edited for brevity. The details of interactions with Dylan (prompt text, error message texts, etc.) will differ among implementations.

The functions format and print are used in some examples but are not part of Dylan.