How to programmatically get the source map for a compiled script?

[Dennis Pagano]

Hi,

I'm compiling many javascript sources programmatically into a single file using the closure compiler. Everything is compiled just fine and works.

However, I can't figure out for the life of me how to programmatically create the source mapping file which would be generated when invoking the compiler from command line using the `--create_source_map` option.

I set the source mapping related options via `setSourceMapFormat()`, `setSourceMapDetailLevel()`, and `setSourceMapOutputPath()`.

After running `compiler.compile()`, I tried to get the mappings using `compiler.getSourceMap().appendTo(sourceMap, fileName)`.

`sourceMap` then contains what seems a legal source mapping - only that it's empty, meaning that there are no mappings in it at all.

Is there any resources on that topic that I did miss? I could only find hints on how to do that via the cli in "Closure - The Definitive Guide", but nothing about how to do it programmatically.

Any help is appreciated.

Thanks in advance,

Dennis