Lystagger

Lystagger is a simplified markup language used to replace HTML. Arbitrary Lystagger code can be embedded in the Jovelyst echo statement. Lystagger syntax, where asterisk (*) means repetition, is defined as follows:

• Tags:
  • [tag]
  • [tag: body]
  • [tag (fld val)*: body]
• Body:
  • text
  • [: text]*
  • [(fld val)*: text]*
• Call Jovelyst code:
  • [expr: <expr>]
  • [exec: <stmt>... ]
  • [lyst: <path>]

Monospace Mode

In monospace mode, all body text rendered to the screens of end-users is in a mono-spaced, typewriter-style font. Every character takes up 2 square cells: an upper cell and a lower cell. Superscripts and subscripts are handled by employing a vertical offset of one square cell. Header text is also mono-spaced, and each character takes up 2 oversized square cells.

Additional Formatting

The grid of characters can be subdivided into panels, which can themselves be subdivided into more panels, and so on. Any panel can contain zero or more text boxes, which may overlap each other. Vertical grid lines each take up one square cell per row of square cells. Horizontal grid lines are displayed in the same pixel row as underscore characters. Any row of square cells containing a horizontal grid line which is 2 pixels wide is taller by exactly one pixel. The following bracket characters: ( ) [ ] { } can be oriented vertically or horizontally, taking up a single column or row of at least 2 square cells, respectively. Widgets such as check boxes, radio buttons, and combo box arrows take up 4 square cells (2 by 2). Images, animations, and diagrams are contained in canvas objects, which can appear anywhere panels can appear.

Rich-Text Mode

In rich-text mode, a given header or paragraph of body text can consist of a single variable-width font. Paragraphs have before/after spacing, left/right indent, and line spacing (single, double, 1.5, etc.). Panels have margins on all 4 sides. In both rich-text and monospace modes, text is rendered to the HTML5 canvas object. Some features like form fields and submit buttons use hidden HTML.