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svg2elm

npm version GitHub license

Generates Elm modules out of SVG files. Comes with a CLI tool and a JavaScript API to build bundler plugins.

Using Parcel? Check out parcel-plugin-elm-svg.

Installation

You can install svg2elm from npm:

$ npm install -g svg2elm

How to use

Let's say we have a chevron icon that we want to embed in our Elm app:

$ cat chevron.svg
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100">
    <line x1="1" y1="1" x2="50" y2="50" stroke-linecap="round" />
    <line x1="50" y1="50" x2="1" y2="99" stroke-linecap="round" />
</svg>

Using svg2elm we can generate an Elm module out of it. Let's call ours Acme.Icons:

$ svg2elm --module Acme.Icons chevron.svg > Acme/Icons.elm
module Acme.Icons exposing (..)

import Svg
import VirtualDom exposing (Attribute, attribute)

chevron : List (Attribute msg) -> Svg.Svg msg
chevron attrs = Svg.node "svg" ([attribute "xmlns" "http://www.w3.org/2000/svg", attribute "viewBox" "0 0 100 100"] ++ attrs) [ Svg.node "line" ([attribute "x1" "1", attribute "y1" "1", attribute "x2" "50", attribute "y2" "50", attribute "stroke-linecap" "round"]) [], Svg.node "line" ([attribute "x1" "50", attribute "y1" "50", attribute "x2" "1", attribute "y2" "99", attribute "stroke-linecap" "round"]) []]

We are now ready to embed the icon in our app! Since the generated function returns an Svg node, we can use it like any other element:

import Acme.Icons exposing (chevron)

...

nextPage =
    button []
        [ text "Next Page"
        , chevron []
        ]

SVG Attributes

Note that the generated function takes a List of Attributes:

chevron : List (Attribute msg) -> Svg.Svg msg

This allows us to tweak our icons in a per usage basis. For example, if we wanted to point our chevron to the left, we could do the following:

previousPage =
    button []
        [ text "Previous Page"
        , chevron [ transform "rotate(180)" ]
        ]

Similarly, we could change the size, colors, stroke width, etc.

...
        , chevron [ width "30", stroke "blue", strokeWidth "2" ]
...

Attributes are appended to the top SVG node. This means that you can only override those set at that level. This is usually not a problem since child nodes inherit parent attributes. However, you might have to tweak your SVG to fit your needs.

Multiple icons per module

You likely want to generate a module with all your app icons. You can do this by passing multiple files to svg2elm:

$ svg2elm --module Acme.Icons icons/chevron.svg icons/user.svg

...or you can use globs:

$ svg2elm --module Acme.Icons icons/*.svg

A function will be generated for each SVG file.

Elm UI

If you're using the awesome mdgriffith/elm-ui, you have to use Element.html to turn your Svg node into an Element.

nextPage =
    button []
        [ text "Next Page"
        , chevron [] |> html
        ]

API

This package also exposes a JavaScript API that can be used to fit svg2elm into any build process.

It's just three functions: reference.

Inspiration

At PINATA, we have been using SVGR for years to load our icons as React components. This project aims to bring the same experience to the world of Elm.

License

BSD-3-Clause. See LICENSE file.

Humans

Thanks to rnons for building elm-svg-parser and Garados007 for making it work with Elm 0.19.

Built by Piotr Brzeziński and Agustín Zubiaga at PINATA.

♥︎