Questions about the network implementation

I'd hope things would have improved with the recent changes to Espruino's variable storage, the minified version doesn't look too big, although:

• adding var f=String.fromCharCode at the start could save you a bunch
  
• looks like some things like mqttPacketLength are public. If they weren't their names would get nicely minified.
  
  

How much is 'that much'? If it's even 10k, that's kind of hard to justify on other boards where MQTT works fine at the moment, and where on the original Espruino I'm starting to have to make space-saving changes just to get releases out the door.

If you really want to include a USE_MQTT kind of thing for ESP8266 it's Open Source so is up to you at the end of the day - but honestly it's unlikely to get included in Espruino board builds. It's also very unlikely to get any bugfixes/contributions from anyone - the JS code tends to get users debugging and fixing problems in it, but C code puts a lot of people off :)

... also right now any constant data (including the symbol table?) will use up RAM, so the MQTT lib will still be eating into available RAM a little all the time on ESP8266.

Having said all that - @JumJum was asking about how contributed code could get built in on-demand. Maybe it's worth trying to come up with a more flexible way of handling that.