Babylon.js - loop through a scene and apply a simple fragment shader to all of the objects
In Javascript

// The suffix of all meshes wich should have the shader applied
var suffix = "shader";

//If true, the shader will be applied on this mesh
var predicate = function(mesh) {
    return (
       mesh.material 
       &amp;&amp; mesh.name.indexOf(suffix , mesh.name.length - suffix.length) !== -1
    );
};

// Creation of the shader material
var shaderMaterial = new BABYLON.ShaderMaterial("sampleShader", scene, "sample", {
            attributes: ["position"],
            uniforms: ["worldViewProjection"]
            });

// Apply the shader on all meshes
scene.meshes.forEach(function(m) {
    if (predicate(m)) {
        m.material = shaderMaterial;
    }
});