The TASM Language Reference Manual Version 1.1 - Synrc

Chapter 3
Syntax
This chapter describes the syntax of the TASM language. The syntax described in this
section covers two types of syntax - plain-text syntax and XML syntax. The syntax
used in the TASM toolset is referred to as the ”plain-text” syntax, which is a format
that can be expressed using formal language constructs, such as a context-free
grammar. This syntax resembles the syntax of popular programming languages. The
plain-text syntax is also the input format for the compiler and the parser. The plain-text
format will also be used to store the content of a TASM specification on the file system.
The XML syntax contains the same content as the plain-text syntax. However, using
XML provides benefits for translation into another language (e.g. the input language of
the model-checker UPPAAL) to interoperate with outside tools. Furthermore, the use
of XML syntax enables easy creation of specification documents in a readable format,
such as HTML. The attributes of both types of syntax are explained in more details in
their respective sections. This chapter contains three sections. Section 3.1 explains the
basic components of the syntax, such as types, operators, reserved words, and comments.
Section 3.2 details the plain-text syntax, using a formal grammar expressed in
Backus-Naur Form (BNF). Section 3.3 explains the XML syntax, using XML syntax
trees.
3.1 Basic Syntax
This section explains the basic syntactical constructs of the TASM language. More
specifically, this section gives the rules for constructing names, gives the list of reserved
keywords, the list of operators, and the general typing rules. Semantical topics, such as
operator precedence are given formally in Chapter 4. The concepts introduced in this
section are applicable to both the plain-text syntax and the XML syntax.
3.1.1 Notational Conventions
The following notational conventions are used in this section and subsequent sections.
• Each abstract type uses the prefix T ASM
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