ES6 tagged template strings for GLSL hex-to-vec3 http://tc39wiki.calculist.org/es6/template-strings/

color-glsl.js

import { getRgb } from 'color-string'

function glsl(strings, ...variables) {
    variables = variables.map(v => {
        var rgb = getRgb(v)
            .map(x => x/255)
            .slice(0, 3)
            .join(', ')
        return `vec3(${rgb})`
    })
    var str = []
    strings.forEach((x, i) => {
        str.push(x)
        str.push(variables[i]||'')
    })
    return str.join('')
}

var background = '#ff0'

var snippet = glsl`
    vec3 color = ${'cyan'};
    gl_FragColor.rgb = ${background};
`
console.log(snippet)

// ... prints ... 
// vec3 color = vec3(0, 1, 1);
// gl_FragColor.rgb = vec3(1, 1, 0);