bin/nijs-build/operations.js
function evaluatePackage(filename, attr, format) {
    var pkgs = require(path.resolve(filename)).pkgs;
    var pkg = pkgs[attr]();
    var expr = nijs.jsToNix(pkg, format);
    return expr;
}
function evaluatePackage(filename, attr, format) {
    var pkgs = require(path.resolve(filename)).pkgs;
    var pkg = pkgs[attr]();
    var expr = nijs.jsToNix(pkg, format);
    return expr;
}
function evaluatePackage ( filename , attr , format ) { var pkgs = require ( path . resolve ( filename ) ) . pkgs ; var pkg = pkgs [ attr ] ( ) ; var expr = nijs . jsToNix ( pkg , format ) ; return expr ; }
Imports the given package composition CommonJS module and evaluates the
specified package.

@param {String} filename Path to the package composition CommonJS module
@param {String} attr Name of the package to evaluate
@param {Boolean} format Indicates whether to nicely format to expression (i.e. generating whitespaces) or not
@return {String} A string containing the generated Nix expression
Imports the given package composition CommonJS module and evaluates the specified package .