Crate termimad[][src]

Expand description

This crate lets you display simple markdown snippets or scrollable wrapped markdown texts in the terminal.

In order to use Termimad you typically need

  • some markdown: a string which you can have loaded or dynamically built
  • a skin: which defines the colors and style attributes of every parts

Additionnaly, you might define an area of the screen in which to draw (and maybe scroll).

The skin

It’s an instance of MadSkin whose fields you customize according to your tastes or (better) to your application’s configuration.

use crossterm::style::{Color::*, Attribute::*};
use termimad::*;

// start with the default skin
let mut skin = MadSkin::default();
// let's decide bold is in light gray
skin.bold.set_fg(gray(20));
// let's make strikeout not striked out but red, with no specific background, and bold
skin.strikeout = CompoundStyle::new(Some(Red), None, Bold.into());

Beware:

  • you may define colors in full rgb but this will limit compatibility with old terminals. It’s recommended to stick to Ansi colors, gray levels, or Crossterm predefined values.
  • styles are composed. For example a word may very well be italic, bold and striked out. It might not be wise to have them differ only by their background color for example.

Display a simple inline snippet

// with the default skin, nothing simpler:
termimad::print_inline("value: **52**");

A multi-line markdown string can be printed the same way than an inline snippet, but you usually want it to be wrapped according to the available terminal width.

eprintln!("{}", skin.term_text(my_markdown));

MadSkin contains other functions to prepare a text for no specific size or for one which isn’t the terminal’s width. It also offers several functions to print it either on stdout or on a given Write.

Display a text, maybe scroll it

A terminal application often uses an alternate screen instead of just dumping its text to stdout, and you often want to display in a specific rect of that screen, with adequate wrapping and not writing outside that rect.

You may also want to display a scrollbar if the text doesn’t fit the area. A MadView makes that simple:

let area = Area::new(0, 0, 10, 12);
let mut view = MadView::from(markdown, area, skin);
view.write().unwrap();

If you don’t want to give ownership of the skin, markdown and area, you may prefer to use a TextView.

You may see how to write a text viewer responding to key inputs to scroll a markdown text in the scrollable example.

Templates

In order to separate the rendering format from the content, the format! macro is not always a good solution because you may not be sure the content is free of characters which may mess the markdown.

A solution is to use one of the templating functions or macros.

Example:

mad_print_inline!(
    &skin,
    "**$0 formula:** *$1*", // the markdown template, interpreted once
    "Disk",  // fills $0
    "2*π*r", // fills $1. Note that the stars don't mess the markdown
);

Main difference with using print!(format!( ... )):

  • the markdown parsing and template building are done only once (using once_cell internally)
  • the given values aren’t interpreted as markdown fragments and don’t impact the style
  • arguments can be omited, repeated, given in any order
  • no support for fmt parameters or arguments other than &str (in the current version)

You’ll find more examples and advice in the templates example.

Examples

The repository contains several other examples, which hopefully cover the whole API while being simple enough. It’s recommended you start by trying them or at least glance at their code.

Re-exports

pub use minimad;

Modules

Macros

ask the user to choose among proposed answers.

print a markdown template, with other arguments taking $0 to $9 places in the template.

write a markdown template, with other arguments taking $0 to $9 places in the template.

Structs

one of the proposed answers to a question

A rectangular part of the screen

A style which may be applied to a compound

wrap a writer to ensure that at most allowed columns are written.

a thread backed event listener emmiting events on a channel.

something to fill with

A fitter can shorten a composite to make it fit a target width without wrapping (by removing parts and replacing them with ellipsis)

Wrap a Minimad Composite, which is a list of Compounds (which are strings with an homogeneous style)

A directly printable markdown snippet, complete with the reference to a skin so that it can implement the Display trait.

a formatted text, implementing Display

A simple input field, managing its cursor position and either handling the events you give it or being managed through direct manipulation functions (put_char, del_char_left, etc.).

A style applicable to a type of line.

A filterable list whose columns can be automatically resized.

A skin defining how a parsed mardkown appears on the terminal (fg and bg colors, bold, italic, underline, etc.)

A MadView is like a textview but it owns everything, from the source markdown to the area and the skin, which often makes it more convenient for dynamic texts. It’s also resizeable.

A pixel precise horizontal bar

a question that can be asked to the user, requiring him to type the key of the desired answer

A scrollbar style defined by two styled chars, one for the track, and one for the thumb.

Information about the fitting of a string into a given width in cols.

A modifiable character which can be easily written or repeated. Can be used for bullets, horizontal rules or quote marks.

A scrollable text, in a specific area.

a user event with happening time

Enums

Left, Center, Right or Unspecified

Termimad error type

A line in a text. This structure should normally not be used outside of the lib.

Statics

Functions

Build an ANSI color

Compute the min and max y (from the top of the terminal, both inclusive) for the thumb part of the scrollbar which would represent the scrolled content in the available height.

Return a reference to the global skin

Build a gray-level color, from 0 (mostly dark) to 23 (light).

Return a formatted line, which implements Display.

Write a string interpreted as markdown with the default skin.

Write a text interpreted as markdown with the default skin.

Build a RGB color

Return a terminal wrapped formatted text, implementing Display.

Return a (width, height) with the dimensions of the available terminal in characters.

Return an unwrapped formatted text, implementing Display.