Sample GulpFile

gulpfile.js

var gulp = require('gulp-help')(require('gulp'));
var argv = require('minimist')(process.argv.slice(2));

gulp.task('minify-js', 'JavaScriptをMinifyします', function() {
  var jsMinify = argv.jsMinify === 'true' ? true :false;
  if(jsMinify){
    console.log('JavaScriptをMinifyするね');
  } else {
    console.log('JavaScriptをMinifyしないよ');
  }
});