TAL Programmer's Guide

Creating Source Files
Getting Started
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Creating Source Files A source file contains source code for your program. The source code can include
declarations, statements, compiler directives, and comments.
You can use a text editor to create a file and to type source code into the file. The
PS Text Edit Reference Manual and the Edit User’s Guide and Reference Manual describe
how to use an editor.
When you enter the source code into the source file, you can use lowercase or
uppercase letters. The compiler does not distinguish between lowercase and
uppercase.
The sample source file shows keywords in uppercase and identifiers in lowercase to
make it easy to see which is which. Keywords are terms that have predefined
meanings to the compiler. Identifiers are names you supply.
The sample source file contains the following kinds of items:
Compiler directives
System procedures
Procedures
Data declarations
Statements
Comments
Compiler Directives Compiler directives let you select compilation options that control various aspects of
the compilation. For example, you can use compiler directives to:
Include source code from other source files
Control the listing
Perform conditional compilation
Check the syntax without generating object code
You can include compiler directives in the source file or in the command to run the
compiler. In the source file, you specify compiler directives in directive lines. Each
directive line begins with a question mark in the leftmost column.
In the sample source file, the SOURCE directive reads the INITIALIZER system
procedure, which handles the startup message (a system message sent to a process
when it starts).