For every key stroke a new immutable string is created with the content of the file/state. Plus data structure for AST/static analysis of every file in the proj

For every key stroke a new immutable string is created with the content of the file/state. Plus data structure for AST/static analysis of every file in the project including dependencies. Plus another copy of the file for rendering with syntax highlight. One would think all this copying of data is very inefficient, but computers are good at moving data around. The most costly is rendering the glyphs.