Terminal control languageTCL overviewParagraph

Paragraph

The paragraph is a macro language allowing execution of TCL statements, looping structures, data stacking, screen input and output, and branching.

A paragraph is an item stored in the current master dictionary whose attribute 1 contains the word paragraph. For compatibility with other vendors, PA and T are also accepted as paragraph indicators.

In its simplest incarnation, a paragraph is a list of TCL commands similar to a standard macro. However, paragraphs also allow other features which make it much more powerful.

Syntax 

tcl.commands
CAUTION:
For compatibility reasons, the syntax rules for this statement are actually a bit more loose than the way they are specified here. New programmers are encouraged to use the suggested syntax as much as possible.

See also

Data stacking, Branching, Macros

  1. Looping
    Paragraphs allow simple loops by starting a block of commands with the loop command and ending that block with the repeat command. The loop command indicates the beginning of a loop in a paragraph.
  2. Data stacking
    As in a macro, paragraphs can stack data by adding a second value after a command. Also, a separate line can display with the syntax:
  3. Screen input/output
    It is possible to solicit input and display output in a paragraph. To do simple output, use the display statement with a string argument. To do simple input, embed the desired prompt within << and >> (double angle brackets). For example, the line display <<Enter name>> prompts Enter name> and then prints the name.
  4. Branching
    For conditional branching, the if-then-go construct is used.
  5. Comments
    Any line beginning with an asterisk is assumed to be a comment. For example, *comment.
  6. Line continuation
    Any line ending with an underscore is merged with the succeeding line when processed by the paragraph processor.
Parent topic: TCL overview