Converting a TypeScript build event into an External Tools command

Question

I'm working on TypeScript files with Visual Studio 2012 Express for Web. Since the Web Essentials addon doesn't work with Express editions, and rebuilding the entire project every time I update a script is starting to take too long, I was hoping to convert the following build event (from the TypeScript project template) into an 'External Tools' command that I can place on my toolbar.

<Target Name="BeforeBuild">
  <Message Text="Compiling TypeScript files" />
  <Message Text="Executing tsc$(TypeScriptSourceMap) @(TypeScriptCompile ->'&quot;%(fullpath)&quot;', ' ')" />
  <Exec Command="tsc$(TypeScriptSourceMap) @(TypeScriptCompile ->'&quot;%(fullpath)&quot;', ' ')" />
</Target>

Unfortunately... this has kinda lost me. I can't find any documentation on $(TypeScriptSourceMap), nor the @() and %() macros. It doesn't seem to appreciate me copying the command directly either. (Even after converting the HTML entities.)

What could I enter into the External Tools dialog in order to mimic this build event?

I'll try to write a PS script or some such as a workaround, but this would lack the functionality of only working on files with the 'TypeScriptCompile' build action.

Answer 1

$(TypeScriptSourceMap) comes from about 4 lines earlier in the project file. It's simply " --sourcemap" when in the debug configuration and "" otherwise.

The @() syntax here basically means "For every project item whose build action is TypeScriptCompile, put its full path in double-quotes and join those resulting items by a space.

An emerging best practice for TypeScript projects is to have a "project.ts" file that looks like this:

project.ts

/// <reference path="file1.ts" />
/// <reference path="file2.ts" />
/// ... and so on

file1.ts

/// <reference path="project.ts" />

class alpha { ... }

file2.ts

/// <reference path="project.ts" />

class beta { ... }

With that setup, you can simply run tsc project.ts or tsc project.ts --out app.ts and the right thing will happen.