Namespace extension ------------------- Iterate over `settings.injections`, doing each injection.
function injectObjects(dest, settings) {
        var injections = settings.injections;
        if (!isArray(injections)) {
            error("Invalid injections array in inject settings");
        }
        var destDecls = dest._declarations;
        for (var i = 0, len = injections.length; i < len; i++) {
            var injection = injections[i];
            if (typeof injection !== "object") {
                error("Invalid injection [" + i + "] in inject settings");
            }
            var destName = injection.name;
            if (!checkUnitName(destName)) {
                error("Invalid injection name '"
                        + destName + "' [" + i + "] in inject settings");
            }
            if (injection.unit != null && injection.value !== undefined) {
                error("Unit and value can't be used together [" + i
                        + "] in inject settings");
            }
            if (injection.unit != null) {
                // Copy unit declaration.
                if (!(settings.namespace instanceof Gumup)) {
                    error("Invalid namespace in inject settings");
                }
                var srcName = injection.unit;
                if (!checkUnitName(srcName)) {
                    error("Invalid unit name '" + srcName
                            + "' [" + i + "] in inject settings");
                }
                var srcDecls = settings.namespace._declarations;
                if (srcDecls[srcName] == null) {
                    error("Unresolvable unit declaration '" + srcName
                            + "' [" + i + "] in inject settigs");
                }
                destDecls[destName] = srcDecls[srcName];
            } else if (injection.value !== undefined) {
                // Inject object as new declaration.
                destDecls[destName] = new Declaration((function(obj) {
                    return function() {
                        return obj;
                    };
                })(injection.value));
            } else {
                error("Invalid injection object [" + i
                        + "] in inject settings");
            }
        }
    }