Distribution · graphics

SVG

Works

SVG written as nested pairs and serialised to the XML — the drawing described as data, so a program that computes a chart or a diagram produces the file without writing angle brackets.

Version: 1.0 github:moritz
Depends: XML::Writer
License: see the source
Its own test suite: 1 file, green
Checked: 2026-09-14 against Raku++ 3.28.0 and Rakudo 2026.08
Where it lives: raku.land · source

Install it #

$ rakupp install SVG

zef install SVG writes the same store; either installer leaves the module usable by both engines.

What it is for #

A chart, a diagram, a generated icon: a drawing that a program computes is a tree of elements with attributes, and SVG is that tree written as XML. The XML is the tedious half. This distribution lets you write the tree as Raku pairs — an element is 'rect' => [ :x(1), :y(2), … ], a pair with an attribute list, and children are more pairs in that list — and turns it into the markup with the SVG namespace declared. It is sixteen lines over XML::Writer, and five distributions build their output on it, SVG::Plot among them.

A drawing as data #

File

use SVG;

say SVG.serialize('svg' => [ :width(20), :height(10),
    'rect' => [ :x(1), :y(2), :width(8), :height(6) ],
    'text' => [ :x(2), :y(9), 'hi' ] ]);
say SVG.serialize('circle' => [ :cx(5), :cy(5), :r(4) ], :!preamble);

Output

<svg xmlns="http://www.w3.org/2000/svg" xmlns:svg="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="20" height="10"><rect x="1" y="2" width="8" height="6" /><text x="2" y="9">hi</text></svg>

<circle cx="5" cy="5" r="4" />

A pair whose value is a list is an element: pairs inside the list are its attributes, further element-pairs are its children, and a bare string is its text. The root gets the three namespace declarations unless :!preamble says otherwise, which is what you want for a fragment that is going to be pasted inside a larger document.

The one thing to know #

Write the attributes as a list, never as a hash. [ :x(1), :y(2) ] is an Array of pairs and keeps its order; { :x(1), :y(2) } is a Hash, and under Rakudo a hash's order is randomised per process, so the same drawing would serialise with its attributes shuffled from one run to the next. The SVG is equivalent either way — an XML parser does not care — but a file that changes on every run cannot be diffed, cached by hash or checked into a repository sensibly. The list form is the idiom the module's author uses and the one every example here uses.