How to use @lerna/npm-install - 2 common examples

actions.push(() => {
        const depsToInstallInRoot = root.some(({ isSatisfied }) => !isSatisfied)
          ? root.map(({ dependency }) => dependency)
          : [];

        if (depsToInstallInRoot.length) {
          tracker.info("hoist", "Installing hoisted dependencies into root");
        }

        const promise = npmInstall.dependencies(rootPkg, depsToInstallInRoot, this.npmConfig);

        return pulseTillDone(promise)
          .then(() =>
            // Link binaries into dependent packages so npm scripts will
            // have access to them.
            pMapSeries(root, ({ name, dependents }) => {
              const { bin } = this.hoistedPackageJson(name);

              if (bin) {
                return pMap(dependents, pkg => {
                  const src = this.hoistedDirectory(name);

                  return symlinkBinary(src, pkg);
                });
              }
            })

actions.push(() => {
          const dependencies = deps.map(({ dependency }) => dependency);
          const promise = npmInstall.dependencies(leafNode.pkg, dependencies, leafNpmConfig);

          return pulseTillDone(promise).then(() => {
            tracker.verbose("installed leaf", leafNode.name);
            tracker.completeWork(1);
          });
        });
      }