To make best use of PipeDream it is important to understand some basic principles of how PipeDream documents are constructed.
Rows and columns
Every document is divided into rows or lines, numbered 1, 2, 3... etc, and one or more columns, labelled with letters A, B, C... etc. Initially the document has 6 columns, labelled A to F, each of which is 12 characters wide, but commands are available for you to alter the widths of individual columns or to alter the number of columns.
The part of a document lying in one row and one column is called a slot. A slot is referred to by its column label and its row number; for example, the following diagram shows slot D3 highlighted by the highlighting bar:
The coordinates of the slot containing the cursor are shown at the top left of the PipeDream screen, and the column containing the cursor is identified by closely- spaced dots on the top border.
The right-hand margin is indicated by the ↓ symbol on the top border, and normally all columns have their right-hand margins at the right-hand edge of the screen.
Much of the power and flexibility of PipeDream comes from the two different types of slot which you can create and combine within a single document: text slots and expression slots. Each type of slot can contain up to 240 characters.
Text slots
Text slots are used for entering and editing continuous text, such as the body of a letter, a technical paper, or a novel.
When working with text, the columns in PipeDream behave as if they are on different layers, like separate overlapping sheets of paper. For example, the initial column format could be represented by the following diagram: