outFile in TS has 2 modes:

First one is a file concatenation. It is enabled when module is anything except system or amd. What it's doing is simply joining all files, without any wrappers or something like that. Because of that everything declared in files is available in all other files (what @tomblind said in a comment above). However, it doesn't allow imports and exports in all files in the project.

The second mode is bundling. It's enabled when module is system or amd. In this mode all files are wrapped in a function that registers modules, but not executes.This mode should be used with some runtime (for example https://requirejs.org/). Loading output compiled with this mode won't execute any module, so user has to call something like require(["entrypointModule"]) manually.

Currently this PR mixes both of these ways, which won't work in a lot of cases I can think of.

package.preload may be used there, but there could be environments without package.

Might have to think about giving the --module option a default value as a value has to be picked but whatever it is it currently has no effect on the output.

I don't think we should change any options implicitly, because if it's not specified in config it won't work with language service anyway.

Sorry, closed it accidentally

Any progress on that? I would like to use it for single output file

I'll look into this some more today

I'm leaving source map tracebacks for bundles out of scope for this PR as I'm not too sure how to proceed with it and this PR is pretty old but does allow --outFile support.

I've added --luaModuleSystem ("none" or "require") as a new option which allows users to generate code that can be used in environments without package or require if they want to output a single file.

Bundling implemented by #750 instead.