Hi. As of now there is no possible way to pass `opt_locations` from typescript for `createProgramInfo` and other similar functions. At the moment of writing, `createProgramInfo` is defined as ``` export function createProgramInfo(gl: WebGLRenderingContext, shaderSources: string[], opt_attribs?: ProgramOptions | string[] | ErrorCallback, opt_errorCallback?: ErrorCallback): ProgramInfo; ``` Thus it has 4 parameters: `gl`, `shaderSources`, `opt_attribs`, `opt_errorCallback` While in reality, the `js` function takes 5 parameters: `gl`, `shaderSources`, `opt_attribs`, `opt_locations`, `opt_errorCallback` ``` function createProgramInfo(gl, shaderSources, opt_attribs, opt_locations, opt_errorCallback) { ```