This makes quickrun, *doom eval* and *Pp Eval Output* buffers behave
better.
Eval output buffers should a) shrink themselves to the size of their
output (within reason), b) *not* grab focus, and c) be easy to close
from afar with C-g/Escape.
Gotchas:
1. Quickrun gets output asynchronously, so we shrink it on
quickrun-after-run-hook, not in the popup rule.
2. *doom eval* and *Pp Eval Output* opens with its output ready, so the
popup system may shrink those to fit.
3. *doom eval* and *Pp Eval Output* handle window selection themselves.
Let them by setting the select window parameter to #'ignore.
+ enable lexical-scope everywhere (lexical-binding = t): ~5-10% faster
startup; ~5-20% general boost
+ reduce consing, function calls & garbage collection by preferring
cl-loop & dolist over lambda closures (for mapc[ar], add-hook, and
various cl-lib filter/map/reduce functions) -- where possible
+ prefer functions with dedicated opcodes, like assq (see byte-defop's
in bytecomp.el for more)
+ prefer pcase & cond (faster) over cl-case
+ general refactor for code readability
+ ensure naming & style conventions are adhered to
+ appease byte-compiler by marking unused variables with underscore
+ defer minor mode activation to after-init, emacs-startup or
window-setup hooks; a customization opportunity for users + ensures
custom functionality won't interfere with startup.
