I have declaration set to true in my tsconfig.json file so I can generate and distribute typings with my library for others consuming the individual modules. (I invoke the TypeScript compiler separately to produce the typings; it wouldn't make sense for rollup-plugin-typescript to generate them for me.)

The TypeScript plugins for Browserify and Webpack seem to ignore this setting, but rollup-plugin-typescript passes it to the TypeScript compiler, resulting in the following error message:

Error loading /Users/jvilk/Code/browserfs/src/browserify_main.ts: Debug Failure. False expression: Unexpected multiple outputs for the file: '/Users/jvilk/Code/browserfs/build/node/browserify_main.d.ts'

After Googling a bit, it appears that this is a limitation of the TypeScript compiler's transpileModule method. Overriding the declaration field to false fixes the problem.

I think it would be great if you chose to do one of the following things:

• Ignore the declaration setting, as it does not appear to be applicable. (But maybe I'm missing a scenario where it would be?), or...
• Preemptively throw a more intelligible error when declaration is set to true.