cord

cord

A cord is a sexy, styled JavaScript String that can print itself prettily.

This project was forked off of percival.

Currently, this involves intelligently handling ANSI escape codes for printing styled strings to terminals; eventually, this should also print identically to HTML source that can be injected into a document.

Usage

cords are created with plain Strings and other cords as child elements. The stylings on nested cords intelligently stack when printed.

Let’s look at some examples. A basic cord just consists of a plain String, and some sort of styling:

sys.puts( cord.beget({ styles : {foreground: 'green'},
                     elements : ["Hello, world!"] }) );

Not too difficult, right? Let’s move on to nesting cord, for more advanced functionality:

sys.puts( cord.beget({ styles : {foreground: 'red'},
                     elements : ["Merry ",
                                 cord.beget({ styles : {foreground: 'green'},
                                            elements : ["Christmas"] }),
                                 "!"] }) );

That, fairly obviously, creates a red cord, containing another (green) cord as a child element. Finally, let’s examine a fairly complex multiply- nested cord:

var c  = cord.beget(), c2 = cord.beget(),
    c3 = cord.beget(), c4 = cord.beget();

c .elements.push('foo ', c2, ' grault');
c2.elements.push('bar ', c3, ' corge');
c3.elements.push('baz ', c4, ' quux');
c4.elements.push(      'qux'      );

c .style({ foreground: 'red'   });    c2.style({ underline: 'single' });
c3.style({ foreground: 'green' });    c4.style({ underline: 'single' });

sys.puts('['+c.toString()+']');

There’s several important things to notice about how that ended up getting displayed:

• The underline effect continued throughout the sub-nested styled strings
• The end of the nested, underlined element did not cause the end of the underline, it was already in effect, and the end of the outer cord with an underline had not yet been reached
• When the end of the green cord had been reached, the red colour was restored (quite a difficult task, using ANSI codes, if I do say so myself!)
• At the culmination of the entire cord, no wayward styles are left over (i.e. the closing bracket is plain white, with no styling)… this is important, as a stray code could screw up the display of everything else in the user’s Terminal

These are the problems with previous, simpler ANSI printers that I was trying to solve with cord. I believe it achieves these goals wonderfully! ^_^