Main Mod Compellation Error

First, sorry if this a duplicate but the other forums weren't helping. Every time I load my code, it wouldn't launch Minecraft and give me the error, main mod compellation error, then proceed me to try to regenerate my code. I've tried deleting most of my work until I last was able to load it in with no avail. The most recent thing I did was trying to make a pickaxe to break bedrock, even after deleting it, it would work, and falling into the void teleports you to a new dimension. It worked fine until this happened. Can someone help me out?