How to use the gulp.task function in gulp

console.log( 'Compiling templates...' );

  gulp.src( sourcePaths.libraryTemplates )
  .pipe( rename( function ( path ) {
    path.dirname = 'templates';
  } ) )
  .pipe( templateCache( libraryName + '-templates.js', {
    module: libraryTemplatesModule,
    standalone: true,
    root: '/' + libraryName + '/'
  } ) )
  .pipe( gulp.dest( buildPaths.root ) );
} );


gulp.task( 'compile-library-styles', function () {

  console.log( 'Compiling styles...' );

  gulp.src( sourcePaths.libraryStyles )
    // The onerror handler prevents Gulp from crashing when you make a mistake in your SASS
  .pipe(sourcemaps.init())
  .pipe( sass( {
    errLogToConsole: true,
    sourceComments: 'map'
  } ) )
  .pipe(sourcemaps.write())
  .pipe( rename( function ( path ) {
    path.dirname = '';
  } ) )
  .pipe( concat( libraryName + '.css' ) )
  .pipe( gulp.dest( buildPaths.root ) );

gulp.task('basic', function() {
  console.log('Toto je task.');
});


/* gulp-src (minimatch) */

gulp.task('src', function() {
  var result = gulp.src('input/*.+(js|txt)');
  console.log('src', result);
});


/* gulp-dest (vinyl) */

gulp.task('dest', function() {
  gulp.src('input/**/*')
    .pipe(gulp.dest('output'));
});


/* gulp-watch */

gulp.task('watch', function() {
  gulp.watch('input/*', function(event) {
    console.log('event', event.type, event.path);
  });
});


/* watch and call task */

import inky     from 'inky';
import fs       from 'fs';
import siphon   from 'siphon-media-query';
import path     from 'path';
import merge    from 'merge-stream';

const $ = plugins();

// Look for the --production flag
const PRODUCTION = !!(yargs.argv.production);
const EMAIL = yargs.argv.to;

gulp.task('build',
  gulp.series(clean, pages, sass, images, inline, cleanCSS));

gulp.task('default',
  gulp.series('build', server, watch));

gulp.task('zip',
  gulp.series('build', zip));

function clean(done) {
  rimraf('dist', done);
}

function cleanCSS(done) {
  rimraf('dist/css', done);
}

// Compile layouts, pages, and partials into flat HTML files
// Then parse using Inky templates
function pages() {

// Update path for OSX
	if (platform === 'osx') destPath += 'node-webkit.app/Contents/Frameworks/node-webkit Framework.framework/Libraries';
	
	// Copy lib
	return gulp.src('./deps/ffmpegsumo/'+platform+'/*')
	.pipe(gulp.dest(destPath));
});

gulp.task('install', ['compile', 'install:ffmpegsumo']);

/* --------------------------------------
 * Tasks to package this app
 * -------------------------------------- */

gulp.task('build', ['compile'], function(cb) {

	// Read package.json
	var package = require('./package.json');

	// Find out which modules to include
	var modules = [];
	if (!!package.dependencies) {
		modules = Object.keys(package.dependencies)
				.filter(function(m) { return m !== 'nodewebkit'; })
				.map(function(m) { return './node_modules/'+m+'/**/*'; });
	}

	// Which platforms should we build
	var platforms = [];
	
	if (process.argv.indexOf('--all') > -1) {

'js:babel',
  ),
);

// Default tasks
gulp.task(
  'default',
  gulp.series(
    'clean',
    'copy',
    'build',
  ),
);

// Development tasks
gulp.task(
  'dev',
  gulp.series(
    'default',
    'watch',
  ),
);

gulp.task('test', [ 'version' ], function () {
	return gulp.src('test-src/index.html')
		.pipe(qunit());
});

gulp.task('minify', [ 'version' ], function () {
	return gulp.src(srcFile)
		.pipe(size({ showFiles: true }))
		.pipe(uglify())
		.pipe(rename('logger.min.js'))
		.pipe(size({ showFiles: true }))
		.pipe(gulp.dest('src'));
});

gulp.task('release', [ 'push_tag', 'publish_npm' ]);

gulp.task('push_tag', function (done) {
	git.tag(version, 'v' + version);
	git.push('origin', 'master', {args: " --tags"}, function (err) {
		done(err);
	});
});

gulp.task('publish_npm', function (done) {
	spawn('npm', [ 'publish' ], { stdio: 'inherit' })
		.on('close', done);
});

gulp.task('default', [ 'version', 'lint', 'test', 'minify' ]);

var DEBUG = process.env.NODE_ENV === 'debug',
	CI = process.env.CI === 'true';

var banner = '/*! <%= pkg.name %> v<%= pkg.version %>, @license <%= pkg.license %>, @link <%= pkg.homepage %> */\n';

var uglifyOptions = {
	compress: {
		drop_console: true
	},
	mangle: {
		except: ['HeadTable', 'NameTable', 'CmapTable', 'HheaTable', 'MaxpTable', 'HmtxTable', 'PostTable', 'OS2Table', 'LocaTable', 'GlyfTable']
	}
};


gulp.task('default', [/*'lint',*/ 'test', 'build', 'buildFonts']);
gulp.task('build', function () {
	var pkg = require('./package.json');
	return gulp.src('src/browser-extensions/pdfMake.js')
		.pipe(webpack(require('./webpack.config.js'), null, reportWebPackErrors))
		.pipe(replace(/\/[*/][@#]\s+sourceMappingURL=((?:(?!\s+\*\/).)*).*\n/g, ''))
		.pipe(header(banner, {pkg: pkg}))
		.pipe(gulp.dest('build'))
		.pipe(sourcemaps.init())
		.pipe(uglify(uglifyOptions))
		.pipe(header(banner, {pkg: pkg}))
		.pipe(rename({extname: '.min.js'}))
		.pipe(sourcemaps.write('./'))
		.pipe(gulp.dest('build'));
});

function reportWebPackErrors(err, stats) {

done();
  } else {
    done('missing `--rule` option');
  }
});

gulp.task('lint', function lint() {
  return gulp
    .src(SRC_FOLDER)
    .pipe(tslint({
      formatter: 'stylish',
    }))
    .pipe(tslint.report());
});

gulp.task('self-lint', function selfLint() {
  return gulp
    .src(SRC_FOLDER)
    .pipe(tslint({
      configuration: 'tslint_eslint_rules.json',
      formatter: 'verbose'
    }))
    .pipe(tslint.report());
});

gulp.task('build', argv.lint === false ? [] : ['lint'], function build(done) {
  var hasError = false;
  gulp
    .src([SRC_FOLDER, DEF_FOLDER])
    .pipe(sourcemaps.init())
    .pipe(tsProject())
    .on('error', function onError() {

'trivial-components.min.js': {
                'maxSize': 100000,
                'maxGzippedSize': 20000
            },
            'trivial-components.min.css': {
                'maxSize': 25000,
                'maxGzippedSize': 5000
            },
            '*': {
                maxTotalSize: 125000,
                maxTotalGzippedSize: 25000
            }
        }));
});

gulp.task('default', ['zip', 'tar', "less-demo", "size-report"]);

gulp.task('watch', function () {
    livereload.listen();
    gulp.watch(['less/*.less', 'demo/less/*.less'], ["less-demo", 'less', 'less-bootstrap']);
});

gulp.task('watch-ts', function () {
	gulp.watch(['ts/*.ts', 'demo/ts/*.ts'], ['js-single', 'typescript-demo']);
});

var tsProject = ts.createProject('tsconfig.json');

gulp.task('typescript', [], function () {
	var tsResult = tsProject.src()
		.pipe(sourcemaps.init())
		.pipe(tsProject());

.pipe(mocha({
            reporter: 'dot'
        }))
});

gulp.task("tslint", () => {
    return gulp.src(["src/**/*.ts", '!src/**/*.d.ts'])
        .pipe(tslint({
            configuration: "./tslint.json"

        }))
        .pipe(tslint.report());
    }
);

gulp.task('dist', ['tslint', 'compile-dist', 'test-dist']);

gulp.task("default", ["tslint", "compile", "test"]);