https://en.m.wikipedia.org/wiki/Static_program_analysis
https://github.com/phpstan/phpstan
https://medium.com/@ondrejmirtes/phpstan-2939cd0ad0e3#.pr2tcgl2d
https://www.patreon.com/phpstan/posts
https://github.com/phpstan/phpstan#class-reflection-extensions
https://github.com/phpstan/phpstan-nette
https://github.com/phpstan/phpstan-doctrine
https://github.com/phpstan/phpstan-dibi
https://github.com/exakat/php-static-analysis-tools