URLForMode callback along with modeURL

[tolmasky]

I have my modes compiled with shasums attached that way I can serve them as immutbale resources (so for example /javascript/javascript-sha256-23958394893040blahblah). This makes the current replacement-based modeURL system difficult to use for dynamically loading modes. I actually currently get away with passing in a fake string object that has a replace method:

CodeMirror.modeURL = { replace: (_, mode) => lookupComplexURLForMode(mode) };

While this works today, it is certainly not ideal as I have to rely on knowledge that replace() gets called. Having modeURL accept a function, or a separate URLForMode option for a callback that returns the URL given a mode would make my code more future-proof.

[marijnh]

Does the path option from attached patch help?

[tolmasky]

Responding here too -- yes this looks good! Thanks!

[marijnh]

Great!