Fix lexer errors in parser tests
Reuse lexer result after checking for lexing success
Merge pull request #74 from jspam/031-lexer-errors-in-parser-tests

Fix lexer errors in parser tests
Implement precedence climbing
Compiler: Buffer output
Merge pull request #82 from Kha/buffer-output

Compiler: Buffer output
Integer -> Int
Merge pull request #83 from jspam/030-precedence-climbing

Implement precedence climbing
Basic AST