Positions

A position is a Lisp object representing the location of one of the characters in the contents of a buffer (see section Buffers). Since Jade stores buffer contents as an array of lines, two index values are needed to reference a single character. A position object contains two integers; the column and line numbers of the character, both these values count upwards from zero (i.e. the first character in a buffer has line and column numbers of zero).

Position objects have no read syntax; they print as,

#<pos column line>

Function: posp object

This function returns t when its argument is a position object.

Function: pos column line

Creates and returns a new position object, it points to column number column and line number line (both integers).

Function: copy-pos pos

Creates a new copy of the position object pos.

• Position Components: Accessing the members of a position
• The Cursor Position: Where the cursor is drawn in the display
• Movement Functions: Position-motion functions
• Positions and Offsets: Converting between positions and buffer offsets

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