TS -> JS + MAP, using gulp, gulp-typescript (without bundling)

gulpfile.js

var ts          = require('gulp-typescript');
var destJS      = './www/dist/js';
var srcTS       = './src/ts';

// TS to JS (without bundling)
// gulp task allowing Typescript debug when JS files are transpiled in another folder
// ref.: https://www.npmjs.com/package/gulp-typescript
gulp.task('tsc', function(){
    gutil.log("=====================");
    gutil.log("TypeScript --> JavaScript (other files)");
    gutil.log("=====================");
    return gulp.src(['./src/ts/**/*.ts', '!./ts/main.ts']) // Exclude the main file (see tsc-main task) (unused finally)
    .pipe(srcmaps.init())
    .pipe(ts({
        target: "ES5",
        module: "commonjs",
        moduleResolution: "node",
        lib:[
            "dom",
            "es2015",
            "es2015.iterable"]
    }))
    .pipe(srcmaps.write('./', {
        destPath: destJS,
        //destPath: destES5,
        base: srcTS
    }))
    .pipe(gulp.dest(destJS));
});